N.

MURIATES were, till the great chemical era of Sir H. Davy’s researches upon chlorine, considered to be compounds of an undecompounded acid, the muriatic, with the different bases; but he proved them to be in reality compounds of chlorine with the metals. They are all, however, still known in commerce by their former appellation. The only muriates much used in the manufactures are,Muriate of ammonia, orSal ammoniac;muriated peroxide of mercury,Mercury,bichloride of;muriate of soda, orchloride of sodium, seeSalt;muriate of tin, seeCalico-printingandTin.

MUSK (Musc, Fr.;Moschus, Germ.), is a peculiar aromatic substance, found in a sac between the navel and the parts of generation of a small male quadruped of the deer kind, called by Linnæus, Moschus moschiferus, which inhabits Tonquin and Thibet. The colour of musk is blackish-brown; it is lumpy or granular, somewhat like dried blood, with which substance, indeed, it is often adulterated. The intensity of its smell is almost the only criterion of its genuineness. When thoroughly dried it becomes nearly scentless; but it recovers its odour when slightly moistened with water of ammonia. The Tonquin musk is most esteemed. It comes to us in small bags covered with a reddish-brown hair; the bag of the Thibet musk is covered with a silver-gray hair. All the analyses of musk hitherto made, teach little or nothing concerning its active or essential constituent. It is used in medicines, and is an ingredient in a great many perfumes.

MUSLIN, is a fine cotton fabric, used for ladies’ robes; which is worn either white, dyed, or printed.

MUST, is the sweet juice of the grape.

MUSTARD (Moutarde, Fr.;Senf, Germ.); is a plant which yields the well-known seed used as a condiment to food. M. Lenormand gives the following prescription for preparing mustard for the table.With 2 pounds of very fine flour of mustard, mix half an ounce of each of the following fresh plants; parsley, chervil, celery, and tarragon, along with a clove of garlic, and twelve salt anchovies, all well minced. The whole is to be triturated with the flour of mustard till the mixture becomes uniform. A little grape-must or sugar is to be added, to give the requisite sweetness; then one ounce of salt, with sufficient water to form a thinnish paste by rubbing in a mortar. With this paste the mustard pots being nearly filled, a redhot poker is to be thrust down into the contents of each, which removes (it is said) some of the acrimony of the mustard, and evaporates a little water, so as to make room for pouring a little vinegar upon the surface of the paste. Such table mustard not only keeps perfectly well, but improves with age.The mode of preparing table mustard patented by M. Soyés, consisted in steeping mustard seed in twice its bulk of weak wood vinegar for eight days, then grinding the whole into paste in a mill, putting it into pots, and thrusting a redhot poker into each of them.

MUSTARD (Moutarde, Fr.;Senf, Germ.); is a plant which yields the well-known seed used as a condiment to food. M. Lenormand gives the following prescription for preparing mustard for the table.

With 2 pounds of very fine flour of mustard, mix half an ounce of each of the following fresh plants; parsley, chervil, celery, and tarragon, along with a clove of garlic, and twelve salt anchovies, all well minced. The whole is to be triturated with the flour of mustard till the mixture becomes uniform. A little grape-must or sugar is to be added, to give the requisite sweetness; then one ounce of salt, with sufficient water to form a thinnish paste by rubbing in a mortar. With this paste the mustard pots being nearly filled, a redhot poker is to be thrust down into the contents of each, which removes (it is said) some of the acrimony of the mustard, and evaporates a little water, so as to make room for pouring a little vinegar upon the surface of the paste. Such table mustard not only keeps perfectly well, but improves with age.

The mode of preparing table mustard patented by M. Soyés, consisted in steeping mustard seed in twice its bulk of weak wood vinegar for eight days, then grinding the whole into paste in a mill, putting it into pots, and thrusting a redhot poker into each of them.

MUTAGE, is a process used in the south of France to arrest the progress of fermentation in the must of the grape. It consists either in diffusing sulphurous acid, from burning sulphur matches in the cask containing the must, or in adding a little sulphite (not sulphate) of lime to it. The last is the best process. SeeFermentation.

MYRICINE, is a vegetable principle which constitutes from 20 to 30 per cent. of the weight of bees-wax, being the residuum from the solvent action of alcohol upon that substance. It is a grayish-white solid, which may be vaporized almost without alteration.

MYRRH, is a gum-resin, which occurs in tears of different sizes; they are reddish-brown, semi-transparent, brittle, of a shining fracture, appear as if greasy under the pestle, they have a very acrid and bitter taste, and a strong, not disagreeable, smell. Myrrh flows from the incisions of a tree not well known, which grows in Arabia and Abyssinia, supposed to be a species ofamyrisormimosa. It consists of resin and gum in proportions stated by Pelletier at 31 of the former and 66 of the latter; but by Braconnot, at 23 and 77. It is used only in medicine.

NACARAT, is a term derived from the Spanish wordnacar, which signifies mother of pearl; and is applied to a pale red colour, with an orange cast. SeeCalico-printing. Thenacaratof Portugal orBezettais a crape or fine linen fabric, dyed fugitively of the above tint, which ladies rub upon their countenances to give them a roseate hue. The Turks of Constantinople manufacture the brightest red crapes of this kind. SeeRouge.

NAILS, MANUFACTURE OF. (Clou, Fr.;Nagel, Germ.)The forging of nails was till of late years a handicraft operation, and therefore belonged to a book of trades, rather than to a dictionary of arts. But several combinations of machinery have been recently employed, under the protection of patents, for making these useful implements, with little or no aid of the human hand; and these deserve to be noticed, on account both of their ingenuity and importance.As nails are objects of prodigious consumption in building their block-houses, the citizens of the United States very early turned their mechanical genius to good account in the construction of various machines for making them. So long since as the year 1810, it appears, from the report of the secretary of their treasury, that they possessed a machine which performed the cutting and heading at one operation, with such rapidity that it could turn out upwards of 100 nails per minute. “Twenty years ago,” says the secretary of the state of Massachusetts, in that report, “some men, then unknown, and then in obscurity, began by cutting slices out of old hoops, and, by a common vice griping these pieces, headed them with several strokes of the hammer. By progressive improvements, slitting-mills were built, and the shears and the heading tools were perfected; yet much labour and expense were requisite to make nails. In a little time Jacob Perkins, Jonathan Ellis, and a few others, put into execution the thought of cutting and of heading nails by water power; but, being more intent upon their machinery than upon their pecuniary affairs, they were unable to prosecute the business. At different times other men have spent fortunes in improvements, and it may be said with truth that more than one millionof dollars has been expended; but at length these joint efforts are crowned with complete success, and we are now able to manufacture, at about one-third of the expense that wrought nails can be manufactured for, nails which are superior to them for at least three-fourths of the purposes to which nails are applied, and for most of those purposes they are full as good. The machines made use of by Odiorne, those invented by Jonathan Ellis, and a few others, present very fine specimens of American genius.“To northern carpenters, it is well known that in almost all instances it is unnecessary to bore a hole before driving a cut nail; all that is requisite is, to place the cutting edge of the nail across the grain of the wood; it is also true, that cut nails will hold better in the wood. These qualities are, in some rough building works, worth twentyper cent.of the value of the article, which is equal to the whole expense of manufacturing. For sheathing and drawing, cut nails are full as good as wrought nails; only in one respect are the best wrought nails a little superior to cut nails, and that is where it is necessary they should be clenched. The manufacture of cut nails was born in our country, and has advanced, within its bosom, through all the various stages of infancy to manhood; and no doubt we shall soon be able, by receiving proper encouragement, to render them superior to wrought nails in every particular.“The principal business of rolling and slitting-mills, is rolling nail plates; they also serve to make nail rods, hoops, tires, sheet iron, and sheet copper. In this State we have not less than twelve.“These mills could roll and slit 7000 tons of iron a year; they now, it is presumed, roll and slit each year about 3500 tons, 2400 tons of which, probably, are cut up into nails and brads, of such a quality that they are good substitutes for hammered nails, and, in fact, have the preference with most people, for the following reasons; viz., on account of the sharp corner and true taper with which cut nails are formed; they may be driven into harder wood without bending or breaking, or hazard of splitting the wood, by which the labour of boring is saved, the nail one way being of the same breadth or thickness from head to point.”Since the year 1820, the following patents have been obtained in England for making nails; many of them of American origin:—Alexander Law, September, 1821, for nails and bolts for ships’ fastenings, made in a twisted form, by hand labour.Glascott and Mitchell, December, 1823, for ship nails with rounded heads, by hand labour.Wilks and Ecroyd, November, 1825, for an engine for cutting wedge-form pieces from plates.Ledsom and Jones, December 11, 1827, for machinery for cutting brads and sprigs from plates; it does not form heads.The first nail apparatus to which I shall particularly advert, is due to Dr. Church; it was patented in his absence by his correspondent, Mr. Thomas Tyndall, of Birmingham, in December, 1827. It consists of two parts; the first is a mode of forming nails, and the shafts of screws, by pinching or pressing ignited rods of iron between indented rollers; the second produces the threads on the shafts of the screws previously pressed. The metallic rods, by being passed between a pair of rollers, are rudely shaped, and then cut asunder between a pair of shears; after which they are pointed and headed, or otherwise brought to their finished forms, by the agency of dies placed in a revolving cylinder. The several parts of the mechanism are worked by toothed wheels, cams, and levers. The second part of Dr. Church’s invention consists of a mechanism for cutting the threads of screws to any degree of obliquity or form.[35][35]For further details, see Newton’s Journal, 2nd series, vol. iii. p. 184.Mr. L. W. Wright’s (American) apparatus should have been mentioned before the preceding, as the patent for it was sealed in March of the same year; though an amended patent was obtained in September, 1828. Its object was to form metal screws for wood. I have seen the machinery, but consider it much too complex to be described in the present work.Mr. Edward Hancorne, of Skinner street, London, nail manufacturer, obtained a patent in October, 1828 for a nail-making machine, of which a brief description may give my readers a conception of this kind of manufacture. Its principles are similar to those of Dr. Church’s more elaborate apparatus.Nail making machineThe rods or bars having been prepared in the usual way, either by rolling or hammering, or by cutting from sheets or plates of iron, called slitting, are then to be made redhot, and in that state passed through the following machine, whereby they are at once cut into suitable lengths, pressed into wedge forms for pointing at the one end, and stamped at the other end to produce the head. A longitudinal view of the machine is shown infig.749.A strong iron frame-work, of which one side is shown ata a, supports the whole of the mechanism.bis a table capable of sliding to and fro horizontally. Uponthis table are the clamps, which lay hold of the sides of the rod as it advances; as also the shears which cut the rod into nail lengths.These clamps or holders consist of a fixed piece and a movable piece; the latter being brought into action by a lever. The rod or bar of iron shown atc, having been made redhot, is introduced into the machine by sliding it forward upon the tableb, when the table is in its most advanced position; rotatory motion is then given to the crank shaftd, by means of a band passing round the rigger pulleye, which causes the tablebto be drawn back by the crank rodf: and as the table recedes, the horizontal lever is acted upon, which closes the clamps. By these means the clamps take fast hold of the sides of the heated rod, and draw it forward, when the movable chap of the shears, also acted upon by a lever, slides laterally, and cuts off the end of the rod held by the clamps: the piece thus separated is destined to form one nail.Suppose that the nail placed atg, having been thus brought into the machine and cut off, is held between clamps, which press it sideways (these clamps are not visible in this view); in this state it is ready to be headed and pointed.Theheaderis a steel dieh, which is to be pressed up against the end of the nail by a cami, upon the crank-shaft; which cam, at this period of the operation, acts against the end of a rodk, forming a continuation of the dieh, and forces up the die, thus compressing the metal into the shape of a nail-head.Thepointingis performed by two rolling snail pieces or spiralsl,l. These pieces are somewhat broader than the breadth of the nail; they turn upon axles in the side frames. As the tablebadvances, the racksm, on the edge of this table, take into the toothed segmentsn,n, upon the axles of the spirals, and cause them to turn round.These spirals pinch the nail at first close under its head with very little force; but as they turn round, the longer radius of the spiral comes into operation upon the nail, so as to press its substance very strongly, and squeeze it into a wedge form. Thus the nail is completed, and is immediately discharged from the clamps or holders. The carriage is then again by the rotation of the crank-shaft, which brings another portion of the rodcforward, cuts it off, and then forms it into a nail.Richard Prosser, July, 1831, for making tacks for ornamental furniture, by soldering or wedging the spike into the head. This also is the invention of Dr. Church.Dr. William Church, February, 1832, for improvements in machinery for making nails. These consist, first, in apparatus for forming rods, bars, or plates of iron, or other metals; secondly, in apparatus for converting the rods, &c., into nails; thirdly, in improvements upon Prosser’s patent. The machinery consists in laminating rollers, and compressing dies.The method of forming the rods from which the nails are to be made, is very advantageous. It consists in passing the bar or plate iron through pressing rollers, which have indentations upon the peripheries of one or both of them, so as to form the bar or plate into the required shape for the rods, which may be afterwards separated into rods of any desired breadth, by common slitting rollers.The principal object of rolling the rods into these wedge forms, is to measure out a quantity of metal duly proportioned to the required thickness or strength of the nail in its several parts; which quantity corresponds to the indentations of the rollers.Thomas John Fuller, February 27, 1834, for an improved apparatus for making square-pointed, and also flat-pointed nails. He claims as his invention, the application of vertical and horizontal hammers (mounted in his machine) combined for the purpose oftapering and forming the points of the nails; which, being made to act alternately, resemble hand work, and are therefore not so apt to injure the fibrous texture of the iron, he imagines, as the rolling machinery is. He finishes the points by rollers.Miles Berry, February 19, 1834, for machinery for forming metal into bolts, rivets, nails and other articles; being a communication from a foreigner residing abroad. He employs in his machine holding chaps, heading dies, toggle joints, cams, &c., mechanisms apparently skilfully contrived, but too complex for admission under the articlenailin this volume.William Southwood Stocker, July, 1836. This is a machine apparently of American parentage, as it has the same set of features as the old American mechanisms of Perkins and Dyer, at the Britannia Nailworks, Birmingham, and all the other American machines since described, for pressing metal into the forms of nails, pins, screw-shafts, rivets, &c.; for example, it possesses pressers or hammers for squeezing the rods of metal, and forming the shanks, which are all worked by a rotatory action; cutters for separating the appropriate lengths, and dies for forming the heads by compression, also actuated by revolving cams or cranks.Mr. Stocker intends, in fact, to effect the same sorts of operations by automatic mechanisms as are usually performed by the hands of a nail-maker with his hammer and anvil; viz., the shaping of a nail from a heated rod of iron, cutting it off at the proper length, and then compressing the end of the metal into the form of the head. His machine may be said to consist of two parts, connected in the same frame; the one for shaping the shank of the nail, the other for cutting it off and heading it. The frame consists of a strong table to bear the machinery. Two pairs of hammers, formed as levers, the one pair made to approach each other by horizontal movements, the other pair by vertical movements, are the implements by which a portion at the end of a redhot rod of iron is beaten or pressed into the wedge-like shape of the shaft of a nail. This having been done, and the rod being still hot, is withdrawn from the beaters, and placed in the other part of the machine, consisting of a pair of jaws like those of a vice, which pinch the shank of the nail and hold it fast. A cutter upon the side of a wheel now comes round, and, by acting as the moving chap of a pair of shears, cuts the nail off from the rod. The nail shank being still firmly held in the jaws of the vice, with a portion of its end projecting outwardly, the heading die is slidden laterally until it comes opposite to the end of the nail; the dye is then projected forward with great force, for the purpose of what is termed upsetting the metal at the projecting end of the nail, and thereby blocking out the head.A main shaft, driven by a band and rigger as usual, brings, as it revolves, a cam into operation upon a lever which carries a double inclined plane or wedge in its front or acting part. This wedge being by the rotatory cam projected forwards between the tails of one of the pairs of hammers, causes the faces of these hammers to approach each other, and to beat or press the redhot iron introduced between them, so as to flatten it upon two opposite sides. The rotatory cam passing round, the wedge lever is relieved, when springs instantly throw back the hammers; another cam and wedge-lever now brings the second pair of hammers to act upon the other two sides of the nail in a similar way. This is repeated several times, until the end of the redhot iron rod, gradually advanced by the hands of the workman, has assumed the desired form, that is, has received the bevel and point of the intended nail.The rod is then withdrawn from between the hammers, and in its heated state is introduced between the jaws of the holders, for cutting off and finishing the nail. A bevel pinion upon the end of the main shaft, takes into and drives a wheel upon a transverse shaft, which carries a cam that works the lever of the holding jaws. The end of the rod being so held in the jaws or vice, a cutter at the side of a wheel upon the transverse shaft separates, as it revolves, the nail from the end of the rod, leaving the nail firmly held by the jaws. By means of a cam, the heading die is now slidden laterally opposite to the end of the nail in the holding jaws, and by another cam, upon the main shaft, the die is forced forward, which compresses the end of the nail, and spreads out the nail into the form of a head. As the main shaft continues to revolve, the cams pass away, and allow the spring to throw the jaws of the vice open, when the nails fall out; but to guard against the chance of a nail sticking in the jaws, a picker is provided, which pushes the nail out as soon as it is finished.In order to produce round shafts, as for screw blanks, bolts, or rivets, the faces of the hammers, and the dies for heading, must be made with suitable concavities.In 1835, 5,180, and in 1836, 5,580 tons of iron nails were exported from the United Kingdom.

NAILS, MANUFACTURE OF. (Clou, Fr.;Nagel, Germ.)

The forging of nails was till of late years a handicraft operation, and therefore belonged to a book of trades, rather than to a dictionary of arts. But several combinations of machinery have been recently employed, under the protection of patents, for making these useful implements, with little or no aid of the human hand; and these deserve to be noticed, on account both of their ingenuity and importance.

As nails are objects of prodigious consumption in building their block-houses, the citizens of the United States very early turned their mechanical genius to good account in the construction of various machines for making them. So long since as the year 1810, it appears, from the report of the secretary of their treasury, that they possessed a machine which performed the cutting and heading at one operation, with such rapidity that it could turn out upwards of 100 nails per minute. “Twenty years ago,” says the secretary of the state of Massachusetts, in that report, “some men, then unknown, and then in obscurity, began by cutting slices out of old hoops, and, by a common vice griping these pieces, headed them with several strokes of the hammer. By progressive improvements, slitting-mills were built, and the shears and the heading tools were perfected; yet much labour and expense were requisite to make nails. In a little time Jacob Perkins, Jonathan Ellis, and a few others, put into execution the thought of cutting and of heading nails by water power; but, being more intent upon their machinery than upon their pecuniary affairs, they were unable to prosecute the business. At different times other men have spent fortunes in improvements, and it may be said with truth that more than one millionof dollars has been expended; but at length these joint efforts are crowned with complete success, and we are now able to manufacture, at about one-third of the expense that wrought nails can be manufactured for, nails which are superior to them for at least three-fourths of the purposes to which nails are applied, and for most of those purposes they are full as good. The machines made use of by Odiorne, those invented by Jonathan Ellis, and a few others, present very fine specimens of American genius.

“To northern carpenters, it is well known that in almost all instances it is unnecessary to bore a hole before driving a cut nail; all that is requisite is, to place the cutting edge of the nail across the grain of the wood; it is also true, that cut nails will hold better in the wood. These qualities are, in some rough building works, worth twentyper cent.of the value of the article, which is equal to the whole expense of manufacturing. For sheathing and drawing, cut nails are full as good as wrought nails; only in one respect are the best wrought nails a little superior to cut nails, and that is where it is necessary they should be clenched. The manufacture of cut nails was born in our country, and has advanced, within its bosom, through all the various stages of infancy to manhood; and no doubt we shall soon be able, by receiving proper encouragement, to render them superior to wrought nails in every particular.

“The principal business of rolling and slitting-mills, is rolling nail plates; they also serve to make nail rods, hoops, tires, sheet iron, and sheet copper. In this State we have not less than twelve.

“These mills could roll and slit 7000 tons of iron a year; they now, it is presumed, roll and slit each year about 3500 tons, 2400 tons of which, probably, are cut up into nails and brads, of such a quality that they are good substitutes for hammered nails, and, in fact, have the preference with most people, for the following reasons; viz., on account of the sharp corner and true taper with which cut nails are formed; they may be driven into harder wood without bending or breaking, or hazard of splitting the wood, by which the labour of boring is saved, the nail one way being of the same breadth or thickness from head to point.”

Since the year 1820, the following patents have been obtained in England for making nails; many of them of American origin:—

Alexander Law, September, 1821, for nails and bolts for ships’ fastenings, made in a twisted form, by hand labour.

Glascott and Mitchell, December, 1823, for ship nails with rounded heads, by hand labour.

Wilks and Ecroyd, November, 1825, for an engine for cutting wedge-form pieces from plates.

Ledsom and Jones, December 11, 1827, for machinery for cutting brads and sprigs from plates; it does not form heads.

The first nail apparatus to which I shall particularly advert, is due to Dr. Church; it was patented in his absence by his correspondent, Mr. Thomas Tyndall, of Birmingham, in December, 1827. It consists of two parts; the first is a mode of forming nails, and the shafts of screws, by pinching or pressing ignited rods of iron between indented rollers; the second produces the threads on the shafts of the screws previously pressed. The metallic rods, by being passed between a pair of rollers, are rudely shaped, and then cut asunder between a pair of shears; after which they are pointed and headed, or otherwise brought to their finished forms, by the agency of dies placed in a revolving cylinder. The several parts of the mechanism are worked by toothed wheels, cams, and levers. The second part of Dr. Church’s invention consists of a mechanism for cutting the threads of screws to any degree of obliquity or form.[35]

[35]For further details, see Newton’s Journal, 2nd series, vol. iii. p. 184.

Mr. L. W. Wright’s (American) apparatus should have been mentioned before the preceding, as the patent for it was sealed in March of the same year; though an amended patent was obtained in September, 1828. Its object was to form metal screws for wood. I have seen the machinery, but consider it much too complex to be described in the present work.

Mr. Edward Hancorne, of Skinner street, London, nail manufacturer, obtained a patent in October, 1828 for a nail-making machine, of which a brief description may give my readers a conception of this kind of manufacture. Its principles are similar to those of Dr. Church’s more elaborate apparatus.

Nail making machine

The rods or bars having been prepared in the usual way, either by rolling or hammering, or by cutting from sheets or plates of iron, called slitting, are then to be made redhot, and in that state passed through the following machine, whereby they are at once cut into suitable lengths, pressed into wedge forms for pointing at the one end, and stamped at the other end to produce the head. A longitudinal view of the machine is shown infig.749.A strong iron frame-work, of which one side is shown ata a, supports the whole of the mechanism.bis a table capable of sliding to and fro horizontally. Uponthis table are the clamps, which lay hold of the sides of the rod as it advances; as also the shears which cut the rod into nail lengths.

These clamps or holders consist of a fixed piece and a movable piece; the latter being brought into action by a lever. The rod or bar of iron shown atc, having been made redhot, is introduced into the machine by sliding it forward upon the tableb, when the table is in its most advanced position; rotatory motion is then given to the crank shaftd, by means of a band passing round the rigger pulleye, which causes the tablebto be drawn back by the crank rodf: and as the table recedes, the horizontal lever is acted upon, which closes the clamps. By these means the clamps take fast hold of the sides of the heated rod, and draw it forward, when the movable chap of the shears, also acted upon by a lever, slides laterally, and cuts off the end of the rod held by the clamps: the piece thus separated is destined to form one nail.

Suppose that the nail placed atg, having been thus brought into the machine and cut off, is held between clamps, which press it sideways (these clamps are not visible in this view); in this state it is ready to be headed and pointed.

Theheaderis a steel dieh, which is to be pressed up against the end of the nail by a cami, upon the crank-shaft; which cam, at this period of the operation, acts against the end of a rodk, forming a continuation of the dieh, and forces up the die, thus compressing the metal into the shape of a nail-head.

Thepointingis performed by two rolling snail pieces or spiralsl,l. These pieces are somewhat broader than the breadth of the nail; they turn upon axles in the side frames. As the tablebadvances, the racksm, on the edge of this table, take into the toothed segmentsn,n, upon the axles of the spirals, and cause them to turn round.

These spirals pinch the nail at first close under its head with very little force; but as they turn round, the longer radius of the spiral comes into operation upon the nail, so as to press its substance very strongly, and squeeze it into a wedge form. Thus the nail is completed, and is immediately discharged from the clamps or holders. The carriage is then again by the rotation of the crank-shaft, which brings another portion of the rodcforward, cuts it off, and then forms it into a nail.

Richard Prosser, July, 1831, for making tacks for ornamental furniture, by soldering or wedging the spike into the head. This also is the invention of Dr. Church.

Dr. William Church, February, 1832, for improvements in machinery for making nails. These consist, first, in apparatus for forming rods, bars, or plates of iron, or other metals; secondly, in apparatus for converting the rods, &c., into nails; thirdly, in improvements upon Prosser’s patent. The machinery consists in laminating rollers, and compressing dies.

The method of forming the rods from which the nails are to be made, is very advantageous. It consists in passing the bar or plate iron through pressing rollers, which have indentations upon the peripheries of one or both of them, so as to form the bar or plate into the required shape for the rods, which may be afterwards separated into rods of any desired breadth, by common slitting rollers.

The principal object of rolling the rods into these wedge forms, is to measure out a quantity of metal duly proportioned to the required thickness or strength of the nail in its several parts; which quantity corresponds to the indentations of the rollers.

Thomas John Fuller, February 27, 1834, for an improved apparatus for making square-pointed, and also flat-pointed nails. He claims as his invention, the application of vertical and horizontal hammers (mounted in his machine) combined for the purpose oftapering and forming the points of the nails; which, being made to act alternately, resemble hand work, and are therefore not so apt to injure the fibrous texture of the iron, he imagines, as the rolling machinery is. He finishes the points by rollers.

Miles Berry, February 19, 1834, for machinery for forming metal into bolts, rivets, nails and other articles; being a communication from a foreigner residing abroad. He employs in his machine holding chaps, heading dies, toggle joints, cams, &c., mechanisms apparently skilfully contrived, but too complex for admission under the articlenailin this volume.

William Southwood Stocker, July, 1836. This is a machine apparently of American parentage, as it has the same set of features as the old American mechanisms of Perkins and Dyer, at the Britannia Nailworks, Birmingham, and all the other American machines since described, for pressing metal into the forms of nails, pins, screw-shafts, rivets, &c.; for example, it possesses pressers or hammers for squeezing the rods of metal, and forming the shanks, which are all worked by a rotatory action; cutters for separating the appropriate lengths, and dies for forming the heads by compression, also actuated by revolving cams or cranks.

Mr. Stocker intends, in fact, to effect the same sorts of operations by automatic mechanisms as are usually performed by the hands of a nail-maker with his hammer and anvil; viz., the shaping of a nail from a heated rod of iron, cutting it off at the proper length, and then compressing the end of the metal into the form of the head. His machine may be said to consist of two parts, connected in the same frame; the one for shaping the shank of the nail, the other for cutting it off and heading it. The frame consists of a strong table to bear the machinery. Two pairs of hammers, formed as levers, the one pair made to approach each other by horizontal movements, the other pair by vertical movements, are the implements by which a portion at the end of a redhot rod of iron is beaten or pressed into the wedge-like shape of the shaft of a nail. This having been done, and the rod being still hot, is withdrawn from the beaters, and placed in the other part of the machine, consisting of a pair of jaws like those of a vice, which pinch the shank of the nail and hold it fast. A cutter upon the side of a wheel now comes round, and, by acting as the moving chap of a pair of shears, cuts the nail off from the rod. The nail shank being still firmly held in the jaws of the vice, with a portion of its end projecting outwardly, the heading die is slidden laterally until it comes opposite to the end of the nail; the dye is then projected forward with great force, for the purpose of what is termed upsetting the metal at the projecting end of the nail, and thereby blocking out the head.

A main shaft, driven by a band and rigger as usual, brings, as it revolves, a cam into operation upon a lever which carries a double inclined plane or wedge in its front or acting part. This wedge being by the rotatory cam projected forwards between the tails of one of the pairs of hammers, causes the faces of these hammers to approach each other, and to beat or press the redhot iron introduced between them, so as to flatten it upon two opposite sides. The rotatory cam passing round, the wedge lever is relieved, when springs instantly throw back the hammers; another cam and wedge-lever now brings the second pair of hammers to act upon the other two sides of the nail in a similar way. This is repeated several times, until the end of the redhot iron rod, gradually advanced by the hands of the workman, has assumed the desired form, that is, has received the bevel and point of the intended nail.

The rod is then withdrawn from between the hammers, and in its heated state is introduced between the jaws of the holders, for cutting off and finishing the nail. A bevel pinion upon the end of the main shaft, takes into and drives a wheel upon a transverse shaft, which carries a cam that works the lever of the holding jaws. The end of the rod being so held in the jaws or vice, a cutter at the side of a wheel upon the transverse shaft separates, as it revolves, the nail from the end of the rod, leaving the nail firmly held by the jaws. By means of a cam, the heading die is now slidden laterally opposite to the end of the nail in the holding jaws, and by another cam, upon the main shaft, the die is forced forward, which compresses the end of the nail, and spreads out the nail into the form of a head. As the main shaft continues to revolve, the cams pass away, and allow the spring to throw the jaws of the vice open, when the nails fall out; but to guard against the chance of a nail sticking in the jaws, a picker is provided, which pushes the nail out as soon as it is finished.

In order to produce round shafts, as for screw blanks, bolts, or rivets, the faces of the hammers, and the dies for heading, must be made with suitable concavities.

In 1835, 5,180, and in 1836, 5,580 tons of iron nails were exported from the United Kingdom.

NANKIN, is a peculiarly coloured cotton cloth, originally manufactured in the above named antient capital of China, from a native cotton of a brown yellow hue. Nankin cloth has been long imitated in perfection by our own manufacturers; and is now exported in considerable quantities from England to Canton. The following is the process for dyeing calico a nankin colour.1. Take 300 pounds of cotton yarn in hanks, being the quantity which four workmen can dye in a day. The yarn for the warp may be about No. 27’s, and that for the weft 23’s or 24’s.2. Foralumingthat quantity, take 10 pounds of saturated alum, free from iron (seeMordant); divide this into two portions; dissolve the first by itself in hot water, so as to form a solution, of spec. grav. 1° Baumé. The second portion is to be reserved for the galling bath.3.Galling, is given with about 80 pounds of oak bark finely ground. This bark may serve for two quantities, if it be applied a little longer the second time.4. Take 30 pounds of fresh slaked quicklime, and form with it a large bath of lime-water.5.Nitro-muriate of tin.For the last bath, 10 or 12 pounds of solution of tin are used, which is prepared as follows:Take 10 pounds of strong nitric acid, and dilute with pure water till its specific gravity be 26° B. Dissolve in it 4633 grains (101⁄2oz. avoird.) of sal ammoniac, and 3 oz. of nitre. Into this solvent, contained in a bottle set in cold water, introduce successively, in very small portions, 28 ounces of grain-tin granulated. This solution, when made, must be kept in a well stoppered bottle.Three coppers are required, one round, about five feet in diameter, and 32 inches deep, for scouring the cotton; 2. two rectangular coppers tinned inside, each 5 feet long and 20 inches deep. Two boxes or cisterns of white wood are to be provided, the one for the lime-water bath, and the other for the solution of tin, each about 7 feet long, 32 inches wide, and 14 inches deep; they are set upon a platform 28 inches high. In the middle between these two chests, a plank is fixed, mounted with twenty-two pegs for wringing the hanks upon, as they are taken out of the bath.6.Aluming.After the cotton yarn has been scoured with water, in the round copper, by being boiled in successive portions of 100 pounds, it must be winced in one of the square tinned coppers, containing two pounds of alum dissolved in 96 gallons of water, at a temperature of 165° F. It is to be then drained over the copper, exposed for some time upon the grass, rinsed in clear water, and wrung.7. Thegalling. Having filled four-fifths of the second square copper with water, 40 pounds of ground oak bark are to be introduced, tied up in a bag of open canvas, and boiled for two hours. The bag being withdrawn, the cotton yarn is to be winced through the boiling tan bath for a quarter of an hour. While the yarn is set to drain above the bath, 28 ounces of alum are to be dissolved in it, and the yarn being once more winced through it for a quarter of an hour, is then taken out, drained, wrung, and exposed to the air. It has now acquired a deep but rather dull yellowish colour, and is ready without washing for the next process.Bablahmay be substituted for oak bark with advantage.8. Theliming. Into the cistern filled with fresh made lime-water, the hanks of cotton yarn suspended upon a series of wooden rods, are to be dipped freely three times in rapid succession; then each hank is to be separately moved by hand through the lime bath, till the desired carmelite shade appear. A weak soda lye may be used instead of lime water.9. Thebrightening, is given by passing the above hanks, after squeezing, rinsing, and airing them, through a dilute bath of solution of tin. The colour thus produced is said to resemble perfectly the nankin of China.Another kind of nankeen colour is given by oxide of iron, precipitated upon the fibre of the cloth, from a solution of the sulphate, by a solution of soda. SeeCalico-printing.

1. Take 300 pounds of cotton yarn in hanks, being the quantity which four workmen can dye in a day. The yarn for the warp may be about No. 27’s, and that for the weft 23’s or 24’s.

2. Foralumingthat quantity, take 10 pounds of saturated alum, free from iron (seeMordant); divide this into two portions; dissolve the first by itself in hot water, so as to form a solution, of spec. grav. 1° Baumé. The second portion is to be reserved for the galling bath.

3.Galling, is given with about 80 pounds of oak bark finely ground. This bark may serve for two quantities, if it be applied a little longer the second time.

4. Take 30 pounds of fresh slaked quicklime, and form with it a large bath of lime-water.

5.Nitro-muriate of tin.For the last bath, 10 or 12 pounds of solution of tin are used, which is prepared as follows:

Take 10 pounds of strong nitric acid, and dilute with pure water till its specific gravity be 26° B. Dissolve in it 4633 grains (101⁄2oz. avoird.) of sal ammoniac, and 3 oz. of nitre. Into this solvent, contained in a bottle set in cold water, introduce successively, in very small portions, 28 ounces of grain-tin granulated. This solution, when made, must be kept in a well stoppered bottle.

Three coppers are required, one round, about five feet in diameter, and 32 inches deep, for scouring the cotton; 2. two rectangular coppers tinned inside, each 5 feet long and 20 inches deep. Two boxes or cisterns of white wood are to be provided, the one for the lime-water bath, and the other for the solution of tin, each about 7 feet long, 32 inches wide, and 14 inches deep; they are set upon a platform 28 inches high. In the middle between these two chests, a plank is fixed, mounted with twenty-two pegs for wringing the hanks upon, as they are taken out of the bath.

6.Aluming.After the cotton yarn has been scoured with water, in the round copper, by being boiled in successive portions of 100 pounds, it must be winced in one of the square tinned coppers, containing two pounds of alum dissolved in 96 gallons of water, at a temperature of 165° F. It is to be then drained over the copper, exposed for some time upon the grass, rinsed in clear water, and wrung.

7. Thegalling. Having filled four-fifths of the second square copper with water, 40 pounds of ground oak bark are to be introduced, tied up in a bag of open canvas, and boiled for two hours. The bag being withdrawn, the cotton yarn is to be winced through the boiling tan bath for a quarter of an hour. While the yarn is set to drain above the bath, 28 ounces of alum are to be dissolved in it, and the yarn being once more winced through it for a quarter of an hour, is then taken out, drained, wrung, and exposed to the air. It has now acquired a deep but rather dull yellowish colour, and is ready without washing for the next process.Bablahmay be substituted for oak bark with advantage.

8. Theliming. Into the cistern filled with fresh made lime-water, the hanks of cotton yarn suspended upon a series of wooden rods, are to be dipped freely three times in rapid succession; then each hank is to be separately moved by hand through the lime bath, till the desired carmelite shade appear. A weak soda lye may be used instead of lime water.

9. Thebrightening, is given by passing the above hanks, after squeezing, rinsing, and airing them, through a dilute bath of solution of tin. The colour thus produced is said to resemble perfectly the nankin of China.

Another kind of nankeen colour is given by oxide of iron, precipitated upon the fibre of the cloth, from a solution of the sulphate, by a solution of soda. SeeCalico-printing.

NAPLES YELLOW (Jaune minéral, Fr.;Neapelgelb, Germ.); is a fine yellow pigment, calledgiallolino, in Italy, where it has been long prepared by a secret process; for few of the recipes which have been published produce a good colour. It is employed not only in oil painting, but also for porcelain and enamel. It has a fresh, brilliant, rich hue, but is apt to be very unequal in different samples.The following prescription has been confidently recommended. Twelve parts of metallic antimony are to be calcined in a reverberatory furnace, along with eight parts of red lead, and four parts of oxide of zinc. These mixed oxides being well rubbed together, are to be fused; and the fused mass is to be triturated and elutriated into a fine powder. Chromate of lead has in a great measure superseded Naples yellow.

The following prescription has been confidently recommended. Twelve parts of metallic antimony are to be calcined in a reverberatory furnace, along with eight parts of red lead, and four parts of oxide of zinc. These mixed oxides being well rubbed together, are to be fused; and the fused mass is to be triturated and elutriated into a fine powder. Chromate of lead has in a great measure superseded Naples yellow.

NAPHTHA, or ROCK-OIL (Huile pétrole, Fr.;Steinöl, Germ.); the Seneca oil of North America, is an ethereous or volatile oil, which is generated within the crust of the earth, and issues in many different localities. The colourless kind, called naphtha, occurs at Baku, near the Caspian Sea, where the vapours which it exhales are kindled, and the flame is applied to domestic and other economical purposes. Wells are also dug in that neighbourhood, in which the naphtha is collected. Similar petroleum wells exist in the territory of the Birmans, at Yananghoung, upon the river Erawaddy, 80 hours’ journey north-east of Pegu, where no less than 520 such springs issue from a pale blue clay, soaked with oil, which rests upon roofing slate. Under the slate is coalcontaining much pyrites. Each spring yields annually 173 casks of 950 pounds each. Petroleum is also found at Amiano in the duchy of Parma, at Saint Zibio in the grand duchy of Modena, at Neufchatel in Switzerland, at Clermont in France, upon some points of the banks of the Iser, at Gabian, a village near Bezières, at Tegernsee in Bavaria, at Val di Noto in Sicily, in Zante, Gallicia, Wallachia, Trinidad, Barbadoes, the United States, Rangoon, near Ava, &c. What is found in the market comes mostly from Trinidad. The city of Parma is lighted with naphtha.The Persian rock-oil is colourless, limpid, very fluid, of a penetrating odour, a hot taste, and a specific gravity of 0·753; it is said to boil at 160° F. The common petroleum has a reddish-yellow colour, which appears blue by reflected light, is transparent, has a spec. grav. of 0·836, and contains, according to Unverdorben, several oils of different degrees of volatility, a little oleine and stearine, resin, with a brown indifferent substance held in solution. By repeated rectifications its density may be reduced to 0·758 at 60° F. Native naphtha, of specific gravity 0·749, is said by some to boil at 201° F. The condensed vapour consists of 85·05 carbon, and 14·30 hydrogen.The naphtha procured by distilling the coal oil of the gas works, is of specific gravity 0·857, boils at 316° F., and consists of, carbon 83·04, hydrogen 12·31, and oxygen 4·65, by my experiments.Rock-oil is very inflammable; its vapour forms with oxygen gas a mixture which violently detonates, and produces water and carbonic acid gas. It does not unite with water, but it imparts a peculiar smell and taste to it; it combines in all proportions with strong alcohol, with ether and oils, both essential and unctuous; it dissolves sulphur, phosphorus, iodine, camphor, most of the resins, wax, fats, and softens caoutchouc into a glairy varnish. When adulterated with oil of turpentine, it becomes thick and reddish brown, on being agitated in contact with strong sulphuric acid. A very fine black pigment may be prepared from the soot of petroleum lamps.

The Persian rock-oil is colourless, limpid, very fluid, of a penetrating odour, a hot taste, and a specific gravity of 0·753; it is said to boil at 160° F. The common petroleum has a reddish-yellow colour, which appears blue by reflected light, is transparent, has a spec. grav. of 0·836, and contains, according to Unverdorben, several oils of different degrees of volatility, a little oleine and stearine, resin, with a brown indifferent substance held in solution. By repeated rectifications its density may be reduced to 0·758 at 60° F. Native naphtha, of specific gravity 0·749, is said by some to boil at 201° F. The condensed vapour consists of 85·05 carbon, and 14·30 hydrogen.

The naphtha procured by distilling the coal oil of the gas works, is of specific gravity 0·857, boils at 316° F., and consists of, carbon 83·04, hydrogen 12·31, and oxygen 4·65, by my experiments.

Rock-oil is very inflammable; its vapour forms with oxygen gas a mixture which violently detonates, and produces water and carbonic acid gas. It does not unite with water, but it imparts a peculiar smell and taste to it; it combines in all proportions with strong alcohol, with ether and oils, both essential and unctuous; it dissolves sulphur, phosphorus, iodine, camphor, most of the resins, wax, fats, and softens caoutchouc into a glairy varnish. When adulterated with oil of turpentine, it becomes thick and reddish brown, on being agitated in contact with strong sulphuric acid. A very fine black pigment may be prepared from the soot of petroleum lamps.

NAPHTHALINE, is a peculiar white crystallizable substance, which may be extracted by distillation from coal tar. It has a pungent aromatic smell and taste, and a specific gravity of 1·048. It is a solid bicarburet of hydrogen, consisting, by my experiments, of 92·9 of carbon, and 7·1 of hydrogen. It has not been applied to any use.

NATRON, is the name of the native sesquicarbonate of soda, which occurs in Egypt, in the west of the Delta; also in the neighbourhood of Fessan, in the province of Sukena in Northern Africa, where it exists under the name ofTrona, crystallized along with sulphate of soda; near Smyrna, in Tartary, Siberia, Hungary, Hindostan, and Mexico. In the last country, there are several natron lakes, a little to the north of Zucatecas, as well as in many other provinces. In Columbia, 48 miles from Merida, native mineral natron is dug up from the bottom of lakes in large quantities, under the name ofUrao.According to Laugier, the Egyptian natron consists of carbonate of soda 22·44, sulphate of soda 18·35, muriate of soda 38·64, water 14·0, insoluble matter 6·0. Trona is composed of carbonate of soda 65·75, sulphate of soda 7·65, muriate of soda 2·63, water 24, insoluble matter 1. The sesquicarbonate may be artificially prepared by boiling for a short time a solution of the bicarbonate.

According to Laugier, the Egyptian natron consists of carbonate of soda 22·44, sulphate of soda 18·35, muriate of soda 38·64, water 14·0, insoluble matter 6·0. Trona is composed of carbonate of soda 65·75, sulphate of soda 7·65, muriate of soda 2·63, water 24, insoluble matter 1. The sesquicarbonate may be artificially prepared by boiling for a short time a solution of the bicarbonate.

NEALING. SeeAnnealing.

NEB-NEB, is the East Indian name ofBablah.

NEEDLE MANUFACTURE. When we consider the simplicity, smallness, and moderate price of a needle, we would be naturally led to suppose that this little instrument requires neither much labour nor complicated manipulations in its construction; but when we learn that every sewing needle, however inconsiderable its size, passes through the hands of 120 different operatives, before it is ready for sale, we cannot fail to be surprised.The best steel, reduced by a wire-drawing machine to the suitable diameter, is the material of which needles are formed. It is brought in bundles to the needle factory, and carefully examined. For this purpose, the ends of a few wires in each bundle are cut off, ignited, and hardened by plunging them into cold water. They are now snapped between the fingers, in order to judge of their quality; the bundles belonging to the most brittle wires are set aside, to be employed in making a peculiar kind of needles.After the quality of the steel wire has been properly ascertained, it is calibred by means of a gauge, to see if it be equally thick and round throughout, for which purpose merely some of the coils of the bundle of wires are tried. Those that are too thick are returned to the wire-drawer, or set apart for another size of needles.Wire unwinding apparatusThe first operation, properly speaking, of the needle factory, is unwinding the bundles of wires. With this view the operative places the coil upon a somewhat conical reel,fig.750., whereon he may fix it at a height proportioned to its diameter. The wire is wound off upon a wheelB, formed of eight equal arms, placed at equal distances round a nave, which is supported by a polished round axle of iron, made fast to a strong uprightC, fixed to the floor of the workshop. Each of the arms is 54 inches long; andone of themD, consists of two parts; of an upper part, which bears the cross barE, to which the wire is applied; and of an under part, connected with the nave. The partEslides in a slot in the fixed partF, and is made fast to it by a peg at a proper height for placing the ends of all the spokes in the circumference of a circle. This arrangement is necessary, to permit the wire to be readily taken off the reel, after being wound tight round its eight branches. The peg is then removed, the branch pushed down, and the coil of wire released.Fig.751.shows the wheel in profile. It is driven by the winch-handleG.ShearsThe new made coil is cut in two points diametrically opposite, either by hand shears, of which one of the branches is fixed in a block by a bolt and a nut, as shown infig.752., or by means of the mechanical shears, represented infig.753.The crankAis moved by a hydraulic wheel, or steam power, and rises and falls alternately. The extremity of this crank enters into a mortise cut in the armBof a bent leverB G C, and is made fast to it by a bolt. An iron rodD F, hinged at one of its extremities to the end of the armC, and at the other to the tail of the shears or chiselE, forces it to open and shut alternately. The operative placed upon the floor underFpresents the coil to the action of the shears, which cut it into two bundles, composed each of 90 or 100 wires, upwards of 8 feet long. The chisel strikes 21 blows in the minute.These bundles are afterwards cut with the same shears into the desired needle lengths, these being regulated by the diameter. For this purpose the wires are put into a semi-cylinder of the proper length, with their ends at the bottom of it, and are all cut across by this gauge. The wires, thus cut, are deposited into a box placed alongside of the workman.Straightening toolsTwo successive incisions are required to cut 100 wires, the third is lost; hence the shears, striking 21 blows in a minute, cut in 10 hours fully 400,000 ends of steel wire, which produce more than 800,000 needles. The wires thus cut are more or less bent, and require to be straightened. This operation is executed with great promptitude, by means of an appropriate instrument. In two strong iron ringsA B,fig.754., of which one is shown in front view atC, 5000 or 6000 wires, closely packed together, are put; and the bundle is placed upon a flat smooth benchL M,fig.757., covered with a cast-iron plateD E, in which there are two grooves of sufficient depth for receiving the two ring bundles of wire, or two openings like the ruleF,fig.757., upon which is placed the open iron ruleF, shown in front infig.756.upon a greater scale. The two rings must be carefully set in the intervals of the rule. By making this rule come and go five or six times with such pressure upon the bundles of wires as causes it to turn upon its axis, all the wires are straightened almost instantaneously.The construction of the machine, represented infig.757., may require explanation. It consists of a frame in the form of a table, of whichL Mis the top; the cast-iron plateD Eis inserted solidly into it. Above the table, seen infig.755.in plan, there are two uprightsC H, to support the cross barA A, which is held in forks cut out in the top of each of the two uprights. This cross barA A, enters tightly into amortise cut in the swing pieceN, at the pointN, where it is fixed by a strong pin, so that the horizontal traverse communicated to the cross barA Aaffects at the same time the swing pieceN. At the bottom of this piece is fixed, as shown in the figure, the open ruleF, seen upon a greater scale infig.756.When the workman wishes to introduce the bundleB, he raises, by means of two chainsI K,fig.757., and the leverG O, the swing piece and the cross bar. For this purpose he draws down the chainI; and when he has placed the bundle properly, so that the two rings enter into the grooveE D,fig.755., he allows the swing piece to fall back, so that the same rings enter the open clefts of the ruleF; he then seizes one of the projecting arms of the cross barA, alternately pulling and pushing it in the horizontal direction, whereby he effects, as already stated, the straightening of the wires.Thumb-pieceThe wires are now taken to the pointing-tools, which usually consist of about 30 grindstones arranged in two rows, driven by a water-wheel. Each stone is about 18 inches in diameter, and 4 inches thick. As they revolve with great velocity, and are liable to fly in pieces, they are partially encased by iron plates, having a proper slit in them to admit of the application of the wires. The workman seated in front of the grindstone, seizes 50 or 60 wires between the thumb and forefinger of his right hand, and directs one end of the bundle to the stone. By means of a bit of stout leather called a thumb-piece, of whichA,fig.758., represents the profile, andBthe plan, the workman presses the wires, and turns them about with his forefinger, giving them such a rotatory motion as to make their points conical. This operation, which is calledroughing down, is dry grinding; because, if water were made use of, the points of the needles would be rapidly rusted. It has been observed long ago, that the siliceous and steel dust thrown off by the stones, was injurious to the eyes and lungs of the grinders; and many methods have been proposed for preventing its bad effects. The machine invented for this purpose by Mr. Prior, for which the Society of Arts voted a premium, deserves to be generally known.Prior's machineA A,fig.759., is the fly-wheel of an ordinary lathe, round which the endless cordB Bpasses, and embraces the pulleyC, mounted upon the axle of the grindstoneD. The flywheel is supported by a strong frameE E, and may be turned by a winch-handle, as usual, or by mechanical power. In the needle factories, the pointing-shops are in general very large, and contain several grindstones running on the same long horizontal shaft, placed near the floor of the apartment, and driven by water or steam power. One of the extremities of the shaft of the wheelAhas a kneed or bent winchF, which by means of an intermediate crankG G, sets in action a double bellowsH I, with a continuous blast, consisting of the air feederHbelow, and the air regulatorIabove. The first is composed of two flaps, one of thema a, being fast and attached to the floor, and the othere e, moving with a hinge-joint; both being joined by strong leather nailed to their edges. This flap has a tailg, of which the end is forked to receive the end of the crankG. Both flaps are perforated with openings furnished with valves for the admission of the air, which is thence driven into a horizontal pipeK, placed beneath the floor of the workshop, and may be afterwards directed in an uninterrupted blast upon the grindstone, by means of the tin tubesN O O, which embrace it, and have longitudinal slits in them. A brass socket is supposed to be fixed upon the ground; it communicates with the pipeK, by means of a small copper tube, into which one of the extremities of the pipeNis fitted; the other is supported by the point of a screwQ, and moves round it as a pivot, so as to allow the two upright branchesO O, to be placed at the same distance from the grindstone. These branches are soldered to the horizontal pipeN, and connected at their top by the tubeP.The wind which escapes through the slits of these pipes, blows upon the grindstone, and carries off its dust into a conduitR,fig.759., which may be extended toS, beyondthe wall of the building, or bent at right angles, as atT, to receive the conduits of the other grindstones of the factory.A safety valveJ, placed in an orifice formed in the regulator flapI, is kept shut by a spiral spring of strong iron wire. It opens to allow the superfluous air to escape, when, by the rising of the bellows, the tailLpresses upon a small piece of wood, and thereby prevents their being injured.Wire holderThe wires thus pointed at both ends are transferred to the first workshop, and cut in two, to form two needles, so that all of one quality may be of equal length. For each sort a small instrument,fig.760., is employed, being a copper plate nearly square, having a turned up edge only upon two of its sides; the one of which is intended to receive all the points, and the other to resist the pressure of the shears. In this small tool a certain number of wires are put with their points in contact with the border, and they are cut together flush with the plate by means of the shears,fig.752., which are moved by the knee of the workman. The remainder of the wires are then laid upon the same copper or brass tool, and are cut also even; there being a trifling waste in this operation. The pieces of wire out of which two needles are formed, are always left a little too long, as the pointer can never hit exact uniformity in his work.These pointed wires are laid parallel to each other in little wooden boxes, and transferred to the head-flattener. This workman, seated at a table with a block of steel before him, about 3 inches cube, seizes in his left hand 20 or 25 needles, between his finger and thumb, spreading them out like a fan, with the points under the thumb, and the heads projecting; he lays these heads upon the steel block, and with a small flat-faced hammer strikes successive blows upon all the heads, so as to flatten each in an instant. He then arranges them in a box with the points turned the same way.The flatted heads have become hardened by the blow of the hammer; when annealed by heating and slow cooling, they are handed to thepiercer. This is commonly a child, who laying the head upon a block of steel, and applying the point of a small punch to it, pierces the eye with a smart tap of a hammer, applied first upon the one side, and then exactly opposite upon the other.Another child trims the eyes, which he does by laying the needle upon a lump of lead, and driving a proper punch through its eye; then laying it sidewise upon a flat piece of steel, with the punch sticking in it, he gives it a tap on each side with his hammer, and causes the eye to take the shape of the punch. The operation of piercing and trimming the eyes, is performed by clever children with astonishing rapidity; who become so dexterous as to pierce with their punch a human hair, and thread it with another, for the amusement of visitors.PincersThe next operative makes the groove at the eye, and rounds the head. He fixes the needle in pincers,fig.761., so that the eye corresponds to their flat side; he then rests the head of the needle in an angular groove, cut in a piece of hard wood fixed in a vice, with the eye in an upright position. He now forms the groove with a single stroke of a small file, dexterously applied, first to the one side of the needle, and then to the other. He next rounds and smooths the head with a small flat file. Having finished, he opens the pincers, throws the needle upon the bench, and puts another in its place. A still more expeditious method of making the grooves and finishing the heads has been long used in most English factories. A small ram is so mounted as to be made to rise and fall by a pedal lever, so that the child works the tool with his foot; in the same way as the heads of pins are fixed. A small die of tempered steel bears the formof the one channel or groove, another similar die, that of the other, both being in relief; these being worked by the lever pedal, finish the grooving of the eye at a single blow, by striking against each other, with the head of the needle between them.The whole of the needles thus prepared are thrown pell-mell into a sort of drawer or box, in which they are by a few dexterous jerks of the workman’s hand made to arrange themselves parallel to each other.The needles are now ready for the tempering; for which purpose they are weighed out in quantities of about 30 pounds, which contain from 250,000 to 500,000 needles, and are carried in boxes to thetemperer. He arranges these upon sheet-iron plates, about 10 inches long, and 5 inches broad, having borders only upon the two longer sides. These plates are heated in a proper furnace to bright redness for the larger needles, and to a less intense degree for the smaller; they are taken out, and inverted smartly over a cistern of water, so that all the needles may be immersed at the same moment, yet distinct from one another. The water being run off from the cistern, the needles are removed, and arranged by agitation in a box, as above described. Instead of heating the needles in a furnace, some manufacturers heat them by means of a bath of melted lead in a state of ignition.After being suddenly plunged in the cold water, they are very hard and excessively brittle. The following mode of tempering them is practised at Neustadt. The needles are thrown into a sort of frying-pan along with a quantity of grease. The pan being placed on the fire, the fatty matter soon inflames, and is allowed to burn out; the needles are now found to be sufficiently well tempered. They must, however, be re-adjusted upon the steel anvil, because many of them get twisted in the hardening and tempering.Polishing bag and tablePolishingis the longest, and not the least expensive process in the needle manufacture. This is done upon bundles containing 500,000 needles; and the same machine under the guidance of one man, polishes from 20 to 30 bundles at a time; either by water or steam power. The needles are rolled up in canvas along with some quartzose sand interstratified between their layers, and the mixture is besmeared with rape-seed oil.Fig.762.represents one of the rolls or packets of needles 12 inches long, strongly bound with cords. These packets are exposed to the to-and-fro pressure of wooden tables, by which they are rolled about, with the effect of causing every needle in the bundle to rub against its fellow, and against the siliceous matter, or emery, enclosed in the bag.Fig.763.represents an improved table for polishing the needles by attrition-bags. The lower tableM Mis movable, whereas in the old constructions it was fixed; the tableChas merely a vertical motion, of pressure upon the bundles, whereas formerly it had both a vertical and horizontal motion. Several bundles may obviously be polished at once in the present machine. The tableM Mmay be of any length that is required, and from 24 to 27 inches broad; resting upon the wooden rollersB,B,B, placed at suitable distances, it receives a horizontal motion, either by hand or other convenient power; the packets of needlesA,A,A, are laid upon it, and over them the tablesC,C,C, which are lifted by means of the chainsK,K,K, and the leversL,L,L, in order to allow the needles to be introduced or removed. The see-saw motion forces therouleauxto turn upon their own axes, and thereby creates such attrition among their contents as to polish them. The workman has merely to distribute these rollsupon the tableM, in a direction perpendicular to that in which the table moves; and whenever one of them gets displaced, he sets it right, lifting by the help of the chain the loaded table. The table makes about 20 horizontal double vibrations in the minute; whereby each bundle, running over 24 inches each time, passes through 40 feet per minute, or 800 yards in the hour.Scouring caskScouring by the cask.After being worked during 18 or 20 hours under the tables, the needles are taken out of the packets, and put into wooden bowls, where they are mixed with sawdust to absorb the black grease upon their surfaces. They are next introduced into a cask,fig.764., and a workman seizing the winchP, turns it round a little; he now puts in some more sawdust at the door,A,B, which is then shut by the claspsG G, and continues the rotation till the needles be quite clean and clear in their eyes; which he ascertains by taking out a sample of them from time to time.Winnowingis the next process, by means of a mechanical ventilator similar to that by which corn is winnowed. The sawdust is blown away, and the grinding powder is separated from the needles, which remain apart clean and bright.The needles are in the next place arranged in order, by being shaken, as above described, in a small somewhat concave iron tray. After being thus laid parallel to each other, they are shaken up against the end of the tray, and accumulated in a nearly upright position, so that they can be seized in a heap and removed in a body upon a pallet knife, with the help of the forefinger.Scouring caskThe preceding five operations, of making up therouleaux, rolling them under the tables, scouring the needles in the cask, winnowing, and arranging them, are repeated ten times in succession, in manufacturing the best articles; the only variation being in the first process. Originally the bundles of needles are formed with alternate layers of siliceous schistus and needles; but after the seventh time, bran freed from flour by sifting is substituted for the schistus. The subsequent four processes are, however, repeated as described. It has been found in England, that emery powder mixed with quartz and mica or pounded granite, is preferable to every thing else for polishing needles at first by attrition in the bags; at the second and following operations, emery mixed with olive oil is used, up to the eighth and ninth, for which putty or oxide of tin with oil is substituted for the emery; at the tenth the putty is used with very little oil; and lastly bran is employed to give a finish. In this mode of operating, the needles arescouredin the copper cask shown in elevationfig.765., and in sectionfig.766.The inner surface of this cask is studded with points to increase the friction among the needles; and a quantity of hot soap suds is repeatedly introduced to wash them clean. The cask must be slowly turned upon its axis, for fear of injuring the mass of needles which it contains. They are finally dried in the wooden cask by attrition with sawdust; then wiped individually with a linen rag or soft leather; when the damaged ones are thrown aside.Sorting ring and handleSorting of the needles.This operation is performed in a dry upper chamber, kept free from damp by proper stoves. Here all the points are first laid the same way; and the needles are then picked out from each other in the order of their polish. The sorting is effected with surprising facility. The workman places 2000 or 3000 needles in an iron ring,fig.767., two inches in diameter, and sets all their heads in one plane; then on looking carefully at their points, he easily recognises the broken ones; and by means of a small hook fixed in a wooden handle,fig.768., he lays hold of the broken needle, and turns it out. These defective needles pass into the hands of another workman, who points them anew upon a grindstone, and they form articles of inferior value. The needles which have got bent in the polishing must now be straightened. The whole are finally arranged exactly according to their lengths by the tact of the finger and thumb of the sorter.The needles are divided into quantities for packing in blue papers, by putting into asmall balance the equivalent weight of 100 needles, and so measuring them out without the trouble of counting them individually.Hone-stoneThebluerreceives these packets, and taking 25 of their needles at a time between the forefinger and thumb, he presses their points against a very small hone-stone of compact micaceous schist, mounted in a little lathe, as shown infig.769., he turns them briskly round, giving the points a bluish cast, while he polishes and improves them. This partial polish is in the direction of the axis; that of the rest of the needle is transverse, which distinguishes the boundaries of the two. The little hone-stone is not cylindrical, but quadrangular, so that it strikes successive blows with its corners upon the needles as it revolves, producing the effect of filing lengthwise. Whenever these angles seem to be blunted, they are set again by thebluer.It is easy to distinguish good English needles from spurious imitations; because the former have their axis coincident with their points, which is readily observed by turning them round between the finger and thumb.The construction of a needle requires, as already stated, about 120 operations; but they are rapidly and uninterruptedly successive. A child cantrimthe eyes of 4000 needles per hour.When we survey a manufacture of this kind, we cannot fail to observe, that the diversity of operations which the needles undergo bears the impress of great mechanical refinement. In the arts, to divide labour, is to abridge it; to multiply operations, is to simplify them; and to attach an operative exclusively to one process, is to render him much more economical and productive.

The best steel, reduced by a wire-drawing machine to the suitable diameter, is the material of which needles are formed. It is brought in bundles to the needle factory, and carefully examined. For this purpose, the ends of a few wires in each bundle are cut off, ignited, and hardened by plunging them into cold water. They are now snapped between the fingers, in order to judge of their quality; the bundles belonging to the most brittle wires are set aside, to be employed in making a peculiar kind of needles.

After the quality of the steel wire has been properly ascertained, it is calibred by means of a gauge, to see if it be equally thick and round throughout, for which purpose merely some of the coils of the bundle of wires are tried. Those that are too thick are returned to the wire-drawer, or set apart for another size of needles.

Wire unwinding apparatus

The first operation, properly speaking, of the needle factory, is unwinding the bundles of wires. With this view the operative places the coil upon a somewhat conical reel,fig.750., whereon he may fix it at a height proportioned to its diameter. The wire is wound off upon a wheelB, formed of eight equal arms, placed at equal distances round a nave, which is supported by a polished round axle of iron, made fast to a strong uprightC, fixed to the floor of the workshop. Each of the arms is 54 inches long; andone of themD, consists of two parts; of an upper part, which bears the cross barE, to which the wire is applied; and of an under part, connected with the nave. The partEslides in a slot in the fixed partF, and is made fast to it by a peg at a proper height for placing the ends of all the spokes in the circumference of a circle. This arrangement is necessary, to permit the wire to be readily taken off the reel, after being wound tight round its eight branches. The peg is then removed, the branch pushed down, and the coil of wire released.Fig.751.shows the wheel in profile. It is driven by the winch-handleG.

Shears

The new made coil is cut in two points diametrically opposite, either by hand shears, of which one of the branches is fixed in a block by a bolt and a nut, as shown infig.752., or by means of the mechanical shears, represented infig.753.The crankAis moved by a hydraulic wheel, or steam power, and rises and falls alternately. The extremity of this crank enters into a mortise cut in the armBof a bent leverB G C, and is made fast to it by a bolt. An iron rodD F, hinged at one of its extremities to the end of the armC, and at the other to the tail of the shears or chiselE, forces it to open and shut alternately. The operative placed upon the floor underFpresents the coil to the action of the shears, which cut it into two bundles, composed each of 90 or 100 wires, upwards of 8 feet long. The chisel strikes 21 blows in the minute.

These bundles are afterwards cut with the same shears into the desired needle lengths, these being regulated by the diameter. For this purpose the wires are put into a semi-cylinder of the proper length, with their ends at the bottom of it, and are all cut across by this gauge. The wires, thus cut, are deposited into a box placed alongside of the workman.

Straightening tools

Two successive incisions are required to cut 100 wires, the third is lost; hence the shears, striking 21 blows in a minute, cut in 10 hours fully 400,000 ends of steel wire, which produce more than 800,000 needles. The wires thus cut are more or less bent, and require to be straightened. This operation is executed with great promptitude, by means of an appropriate instrument. In two strong iron ringsA B,fig.754., of which one is shown in front view atC, 5000 or 6000 wires, closely packed together, are put; and the bundle is placed upon a flat smooth benchL M,fig.757., covered with a cast-iron plateD E, in which there are two grooves of sufficient depth for receiving the two ring bundles of wire, or two openings like the ruleF,fig.757., upon which is placed the open iron ruleF, shown in front infig.756.upon a greater scale. The two rings must be carefully set in the intervals of the rule. By making this rule come and go five or six times with such pressure upon the bundles of wires as causes it to turn upon its axis, all the wires are straightened almost instantaneously.

The construction of the machine, represented infig.757., may require explanation. It consists of a frame in the form of a table, of whichL Mis the top; the cast-iron plateD Eis inserted solidly into it. Above the table, seen infig.755.in plan, there are two uprightsC H, to support the cross barA A, which is held in forks cut out in the top of each of the two uprights. This cross barA A, enters tightly into amortise cut in the swing pieceN, at the pointN, where it is fixed by a strong pin, so that the horizontal traverse communicated to the cross barA Aaffects at the same time the swing pieceN. At the bottom of this piece is fixed, as shown in the figure, the open ruleF, seen upon a greater scale infig.756.

When the workman wishes to introduce the bundleB, he raises, by means of two chainsI K,fig.757., and the leverG O, the swing piece and the cross bar. For this purpose he draws down the chainI; and when he has placed the bundle properly, so that the two rings enter into the grooveE D,fig.755., he allows the swing piece to fall back, so that the same rings enter the open clefts of the ruleF; he then seizes one of the projecting arms of the cross barA, alternately pulling and pushing it in the horizontal direction, whereby he effects, as already stated, the straightening of the wires.

Thumb-piece

The wires are now taken to the pointing-tools, which usually consist of about 30 grindstones arranged in two rows, driven by a water-wheel. Each stone is about 18 inches in diameter, and 4 inches thick. As they revolve with great velocity, and are liable to fly in pieces, they are partially encased by iron plates, having a proper slit in them to admit of the application of the wires. The workman seated in front of the grindstone, seizes 50 or 60 wires between the thumb and forefinger of his right hand, and directs one end of the bundle to the stone. By means of a bit of stout leather called a thumb-piece, of whichA,fig.758., represents the profile, andBthe plan, the workman presses the wires, and turns them about with his forefinger, giving them such a rotatory motion as to make their points conical. This operation, which is calledroughing down, is dry grinding; because, if water were made use of, the points of the needles would be rapidly rusted. It has been observed long ago, that the siliceous and steel dust thrown off by the stones, was injurious to the eyes and lungs of the grinders; and many methods have been proposed for preventing its bad effects. The machine invented for this purpose by Mr. Prior, for which the Society of Arts voted a premium, deserves to be generally known.

Prior's machine

A A,fig.759., is the fly-wheel of an ordinary lathe, round which the endless cordB Bpasses, and embraces the pulleyC, mounted upon the axle of the grindstoneD. The flywheel is supported by a strong frameE E, and may be turned by a winch-handle, as usual, or by mechanical power. In the needle factories, the pointing-shops are in general very large, and contain several grindstones running on the same long horizontal shaft, placed near the floor of the apartment, and driven by water or steam power. One of the extremities of the shaft of the wheelAhas a kneed or bent winchF, which by means of an intermediate crankG G, sets in action a double bellowsH I, with a continuous blast, consisting of the air feederHbelow, and the air regulatorIabove. The first is composed of two flaps, one of thema a, being fast and attached to the floor, and the othere e, moving with a hinge-joint; both being joined by strong leather nailed to their edges. This flap has a tailg, of which the end is forked to receive the end of the crankG. Both flaps are perforated with openings furnished with valves for the admission of the air, which is thence driven into a horizontal pipeK, placed beneath the floor of the workshop, and may be afterwards directed in an uninterrupted blast upon the grindstone, by means of the tin tubesN O O, which embrace it, and have longitudinal slits in them. A brass socket is supposed to be fixed upon the ground; it communicates with the pipeK, by means of a small copper tube, into which one of the extremities of the pipeNis fitted; the other is supported by the point of a screwQ, and moves round it as a pivot, so as to allow the two upright branchesO O, to be placed at the same distance from the grindstone. These branches are soldered to the horizontal pipeN, and connected at their top by the tubeP.

The wind which escapes through the slits of these pipes, blows upon the grindstone, and carries off its dust into a conduitR,fig.759., which may be extended toS, beyondthe wall of the building, or bent at right angles, as atT, to receive the conduits of the other grindstones of the factory.

A safety valveJ, placed in an orifice formed in the regulator flapI, is kept shut by a spiral spring of strong iron wire. It opens to allow the superfluous air to escape, when, by the rising of the bellows, the tailLpresses upon a small piece of wood, and thereby prevents their being injured.

Wire holder

The wires thus pointed at both ends are transferred to the first workshop, and cut in two, to form two needles, so that all of one quality may be of equal length. For each sort a small instrument,fig.760., is employed, being a copper plate nearly square, having a turned up edge only upon two of its sides; the one of which is intended to receive all the points, and the other to resist the pressure of the shears. In this small tool a certain number of wires are put with their points in contact with the border, and they are cut together flush with the plate by means of the shears,fig.752., which are moved by the knee of the workman. The remainder of the wires are then laid upon the same copper or brass tool, and are cut also even; there being a trifling waste in this operation. The pieces of wire out of which two needles are formed, are always left a little too long, as the pointer can never hit exact uniformity in his work.

These pointed wires are laid parallel to each other in little wooden boxes, and transferred to the head-flattener. This workman, seated at a table with a block of steel before him, about 3 inches cube, seizes in his left hand 20 or 25 needles, between his finger and thumb, spreading them out like a fan, with the points under the thumb, and the heads projecting; he lays these heads upon the steel block, and with a small flat-faced hammer strikes successive blows upon all the heads, so as to flatten each in an instant. He then arranges them in a box with the points turned the same way.

The flatted heads have become hardened by the blow of the hammer; when annealed by heating and slow cooling, they are handed to thepiercer. This is commonly a child, who laying the head upon a block of steel, and applying the point of a small punch to it, pierces the eye with a smart tap of a hammer, applied first upon the one side, and then exactly opposite upon the other.

Another child trims the eyes, which he does by laying the needle upon a lump of lead, and driving a proper punch through its eye; then laying it sidewise upon a flat piece of steel, with the punch sticking in it, he gives it a tap on each side with his hammer, and causes the eye to take the shape of the punch. The operation of piercing and trimming the eyes, is performed by clever children with astonishing rapidity; who become so dexterous as to pierce with their punch a human hair, and thread it with another, for the amusement of visitors.

Pincers

The next operative makes the groove at the eye, and rounds the head. He fixes the needle in pincers,fig.761., so that the eye corresponds to their flat side; he then rests the head of the needle in an angular groove, cut in a piece of hard wood fixed in a vice, with the eye in an upright position. He now forms the groove with a single stroke of a small file, dexterously applied, first to the one side of the needle, and then to the other. He next rounds and smooths the head with a small flat file. Having finished, he opens the pincers, throws the needle upon the bench, and puts another in its place. A still more expeditious method of making the grooves and finishing the heads has been long used in most English factories. A small ram is so mounted as to be made to rise and fall by a pedal lever, so that the child works the tool with his foot; in the same way as the heads of pins are fixed. A small die of tempered steel bears the formof the one channel or groove, another similar die, that of the other, both being in relief; these being worked by the lever pedal, finish the grooving of the eye at a single blow, by striking against each other, with the head of the needle between them.

The whole of the needles thus prepared are thrown pell-mell into a sort of drawer or box, in which they are by a few dexterous jerks of the workman’s hand made to arrange themselves parallel to each other.

The needles are now ready for the tempering; for which purpose they are weighed out in quantities of about 30 pounds, which contain from 250,000 to 500,000 needles, and are carried in boxes to thetemperer. He arranges these upon sheet-iron plates, about 10 inches long, and 5 inches broad, having borders only upon the two longer sides. These plates are heated in a proper furnace to bright redness for the larger needles, and to a less intense degree for the smaller; they are taken out, and inverted smartly over a cistern of water, so that all the needles may be immersed at the same moment, yet distinct from one another. The water being run off from the cistern, the needles are removed, and arranged by agitation in a box, as above described. Instead of heating the needles in a furnace, some manufacturers heat them by means of a bath of melted lead in a state of ignition.

After being suddenly plunged in the cold water, they are very hard and excessively brittle. The following mode of tempering them is practised at Neustadt. The needles are thrown into a sort of frying-pan along with a quantity of grease. The pan being placed on the fire, the fatty matter soon inflames, and is allowed to burn out; the needles are now found to be sufficiently well tempered. They must, however, be re-adjusted upon the steel anvil, because many of them get twisted in the hardening and tempering.

Polishing bag and table

Polishingis the longest, and not the least expensive process in the needle manufacture. This is done upon bundles containing 500,000 needles; and the same machine under the guidance of one man, polishes from 20 to 30 bundles at a time; either by water or steam power. The needles are rolled up in canvas along with some quartzose sand interstratified between their layers, and the mixture is besmeared with rape-seed oil.Fig.762.represents one of the rolls or packets of needles 12 inches long, strongly bound with cords. These packets are exposed to the to-and-fro pressure of wooden tables, by which they are rolled about, with the effect of causing every needle in the bundle to rub against its fellow, and against the siliceous matter, or emery, enclosed in the bag.Fig.763.represents an improved table for polishing the needles by attrition-bags. The lower tableM Mis movable, whereas in the old constructions it was fixed; the tableChas merely a vertical motion, of pressure upon the bundles, whereas formerly it had both a vertical and horizontal motion. Several bundles may obviously be polished at once in the present machine. The tableM Mmay be of any length that is required, and from 24 to 27 inches broad; resting upon the wooden rollersB,B,B, placed at suitable distances, it receives a horizontal motion, either by hand or other convenient power; the packets of needlesA,A,A, are laid upon it, and over them the tablesC,C,C, which are lifted by means of the chainsK,K,K, and the leversL,L,L, in order to allow the needles to be introduced or removed. The see-saw motion forces therouleauxto turn upon their own axes, and thereby creates such attrition among their contents as to polish them. The workman has merely to distribute these rollsupon the tableM, in a direction perpendicular to that in which the table moves; and whenever one of them gets displaced, he sets it right, lifting by the help of the chain the loaded table. The table makes about 20 horizontal double vibrations in the minute; whereby each bundle, running over 24 inches each time, passes through 40 feet per minute, or 800 yards in the hour.

Scouring cask

Scouring by the cask.After being worked during 18 or 20 hours under the tables, the needles are taken out of the packets, and put into wooden bowls, where they are mixed with sawdust to absorb the black grease upon their surfaces. They are next introduced into a cask,fig.764., and a workman seizing the winchP, turns it round a little; he now puts in some more sawdust at the door,A,B, which is then shut by the claspsG G, and continues the rotation till the needles be quite clean and clear in their eyes; which he ascertains by taking out a sample of them from time to time.

Winnowingis the next process, by means of a mechanical ventilator similar to that by which corn is winnowed. The sawdust is blown away, and the grinding powder is separated from the needles, which remain apart clean and bright.

The needles are in the next place arranged in order, by being shaken, as above described, in a small somewhat concave iron tray. After being thus laid parallel to each other, they are shaken up against the end of the tray, and accumulated in a nearly upright position, so that they can be seized in a heap and removed in a body upon a pallet knife, with the help of the forefinger.

Scouring cask

The preceding five operations, of making up therouleaux, rolling them under the tables, scouring the needles in the cask, winnowing, and arranging them, are repeated ten times in succession, in manufacturing the best articles; the only variation being in the first process. Originally the bundles of needles are formed with alternate layers of siliceous schistus and needles; but after the seventh time, bran freed from flour by sifting is substituted for the schistus. The subsequent four processes are, however, repeated as described. It has been found in England, that emery powder mixed with quartz and mica or pounded granite, is preferable to every thing else for polishing needles at first by attrition in the bags; at the second and following operations, emery mixed with olive oil is used, up to the eighth and ninth, for which putty or oxide of tin with oil is substituted for the emery; at the tenth the putty is used with very little oil; and lastly bran is employed to give a finish. In this mode of operating, the needles arescouredin the copper cask shown in elevationfig.765., and in sectionfig.766.The inner surface of this cask is studded with points to increase the friction among the needles; and a quantity of hot soap suds is repeatedly introduced to wash them clean. The cask must be slowly turned upon its axis, for fear of injuring the mass of needles which it contains. They are finally dried in the wooden cask by attrition with sawdust; then wiped individually with a linen rag or soft leather; when the damaged ones are thrown aside.

Sorting ring and handle

Sorting of the needles.This operation is performed in a dry upper chamber, kept free from damp by proper stoves. Here all the points are first laid the same way; and the needles are then picked out from each other in the order of their polish. The sorting is effected with surprising facility. The workman places 2000 or 3000 needles in an iron ring,fig.767., two inches in diameter, and sets all their heads in one plane; then on looking carefully at their points, he easily recognises the broken ones; and by means of a small hook fixed in a wooden handle,fig.768., he lays hold of the broken needle, and turns it out. These defective needles pass into the hands of another workman, who points them anew upon a grindstone, and they form articles of inferior value. The needles which have got bent in the polishing must now be straightened. The whole are finally arranged exactly according to their lengths by the tact of the finger and thumb of the sorter.

The needles are divided into quantities for packing in blue papers, by putting into asmall balance the equivalent weight of 100 needles, and so measuring them out without the trouble of counting them individually.

Hone-stone

Thebluerreceives these packets, and taking 25 of their needles at a time between the forefinger and thumb, he presses their points against a very small hone-stone of compact micaceous schist, mounted in a little lathe, as shown infig.769., he turns them briskly round, giving the points a bluish cast, while he polishes and improves them. This partial polish is in the direction of the axis; that of the rest of the needle is transverse, which distinguishes the boundaries of the two. The little hone-stone is not cylindrical, but quadrangular, so that it strikes successive blows with its corners upon the needles as it revolves, producing the effect of filing lengthwise. Whenever these angles seem to be blunted, they are set again by thebluer.

It is easy to distinguish good English needles from spurious imitations; because the former have their axis coincident with their points, which is readily observed by turning them round between the finger and thumb.

The construction of a needle requires, as already stated, about 120 operations; but they are rapidly and uninterruptedly successive. A child cantrimthe eyes of 4000 needles per hour.

When we survey a manufacture of this kind, we cannot fail to observe, that the diversity of operations which the needles undergo bears the impress of great mechanical refinement. In the arts, to divide labour, is to abridge it; to multiply operations, is to simplify them; and to attach an operative exclusively to one process, is to render him much more economical and productive.

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