Image unavailable: SUCKERS OF CUTTLE. LIMPET. STAR-FISH. SUCKING-FISH. FOOT OF GECKO. LAMPERN. CUPPING-GLASS. PNEUMATIC PEG. SUCKER. MAGDEBURG HEMISPHERES.SUCKERS OF CUTTLE. LIMPET. STAR-FISH. SUCKING-FISH. FOOT OF GECKO. LAMPERN. CUPPING-GLASS. PNEUMATIC PEG. SUCKER. MAGDEBURG HEMISPHERES.
Thelower figure represents the instrument called the Magdeburg Hemispheres, which are made for the purpose of showing the enormous power of air-pressure. They are two hollowed hemispheres, having their edges very accurately ground together. When used, a little lard is rubbed on the edges in order to insure their exact fit, and they are thenpressed tightly together. The air is removed by means of the common exhausting syringe, and it is found that the two adhere together with such force that two strong men cannot pull them asunder. But, if the tap be turned, and air admitted, they come apart without the least difficulty.
Similarly, if two plates of glass or metal be ground to exactly plane surfaces, and pressed together, they adhere nearly as strongly as if they were one solid piece.
Wewill now turn from Art to Nature, and examine some natural producers of vacuum.
One of the most celebrated is that series of suckers which may be found upon the arms of the various Cuttles. At the upper part of the illustration a figure is given of part of an arm, on which are four suckers. When the animal wishes to attach itself to any object, it presses the disc of the sucker against it, and simultaneously withdraws the centre, exactly as the boy does with his toy sucker. And, as each arm contains a great number of suckers, it is evident that the holding power must be very great. Indeed, on one occasion when a comparatively small specimen had fastened on a man’s arm, he could not remove it, but was obliged to have it cut away piecemeal by an assistant.
The common Water-beetle has similar suckers upon its first pair of feet, and can adhere to smooth surfaces with great tenacity.
Onthe left of the cuttle-arm is the common Limpet, shown as it appears when adhering to the rocks. Every visitor to the seaside who has attempted to remove the Limpets may remember how difficult it is to stir them when they have once taken their hold. If they can be taken by surprise, they come away with a touch; but if they become alarmed, they press the edges of the foot firmly against the rock, withdraw the centre, and thus create the necessary vacuum.
Nextfollows a Star-fish, shown as it appears when in the act of walking, or rather, gliding along.
This movement is obtained by the use of a vast number of long suckers, exactly resembling the pneumatic peg, exceptthat they are flexible, and can be curved in any direction. It is really beautiful to see the manner in which a Star-fish will glide along by means of its suckers, its arms accommodating themselves to the irregularities of the ground, and its multitudinous suckers protruded and withdrawn with a never-ceasing movement.
And, as the Star-fish is apparently blind, not having any organs which can even be conjectured to serve the purpose of vision, this mode of directing its course is not easily understood. Yet, blind though it may be, it guides itself with as much accuracy as if it possessed eyes, and evidently does so with a definite purpose, using its suckers with as much decision as a centipede uses its legs.
These suckers can be seen very well by placing a Star-fish in a shallow vessel of sea-water, and laying it on its back. The suckers immediately protrude themselves from their little apertures, and the arms slowly curve themselves so as to find something to which the suckers can adhere. Presently one or two of the suckers will take hold of the bottom of the vessel. Others soon follow, and in a very short time the Star-fish is on its legs, if we may so call them, and is quietly gliding on its way.
Belowthe Star-fish is seen the celebrated Sucking-fish (Echeneis remora) about which so many strange tales have been told, and which is possessed of a structure remarkable enough to need no aid from invention. The dorsal fin of this fish is modified in a most singular manner. The spines of which it is so largely composed are metamorphosed into flattened plates very much resembling the laths of a Venetian blind, and form an instrument of suction identical in principle, though not in form, with those which have already been described. When the sucker is pressed against a smooth surface, a vacuum is formed, and the fish in consequence adheres firmly to the object.
The fact has been known for centuries, though it has only been lately discovered, that the sucker was not a separate apparatus, but merely one of the fins modified in a simple though effective manner. Indeed, any one who has some slight notion of the structure of a fin can easily see, by lookingat the Sucking-fish from above, that the apparatus is nothing more than the dorsal fin laid flat.
I may mention here that the name of Echeneis is taken from two words signifying “ship-holder.” It was given to the fish on account of a curious notion which was fully believed until quite modern times, that the Sucking-fish had the power of attaching itself to ships, and holding them so firmly that they could not proceed in spite of sails and oars. The word Echeneis is used by Aristotle in his “History of Animals.” The specific nameremora, or “delay,” is Latin, and is given to the fish for the same reason.
The little Gobies, which are so plentiful along our coasts, have the ventral fins formed into a sucker, with which they can cling firmly to any object, such as a leaf of seaweed or a smooth rock or stone. A similar modification of the ventral fins is also found in the beautifully coloured Lump-fish, or Lump-sucker, sometimes called the Cock-paidle. One of these fishes, when placed in a bucket of water, adhered so strongly to the bottom, that, when lifted by the tail, it bore the whole weight of the pail and water.
Justbelow the Sucking-fish is drawn a foot of the curious little lizard, the Gecko, so called from its peculiar cry. It is common in the West Indies, and haunts houses, traversing their walls just as flies run up panes of glass. It is enabled to perform this movement by means of the structure of the feet. As the reader may see by reference to the illustration, the toes are greatly widened and flattened. If the lower surface be examined, it will be found to be furnished with a number of plates very much resembling those of the sucking-fish, and performing the same office.
So rapid is the operation of these plates, that the animal can even leap upon a perpendicular flat surface, and stick there. Perhaps the reader may remember that the beautiful Tree-frogs, which cling so tightly to leaves, are furnished with suckers on their toes, whereby they can hold on even to an upright pane of glass. In fact, the smooth surface of the glass seems to please them, and when they adhere to it they give an excellent opportunity of examining the structure of the feet with a magnifying-glass.
Another example of the pressure of the atmosphere has been slightly mentioned, when treating of the ball-and-socket joint. This is the joint by which the thigh-bone is attached to the hip. As the rounded head of the thigh-bone fits exactly into the cavity of the hip, and is, moreover, well lubricated with the animal oil called synovia, no air can obtain admission between the two. Consequently, they are held together so firmly by the pressure of the atmosphere, that they retain their places even after the whole of the muscular attachments have been removed. Not without very great force can the thigh-bone be dislodged from the shallow socket in which it lies; but, if a hole be bored so as to admit the air, it comes out at once.
Similarly, however firmly a limpet may cling to the rock, if the finest needle were introduced so as to admit air, the creature could not retain its hold for a moment.
Thelast figure on the illustration represents the common Lampern (Lampetra fluviatilis).
The mouth of this little fish is formed on the principle of the sucker, and very firmly it can adhere, as I can state from much personal experience. Indeed, it is rather alarming, to those who are unacquainted with the character of the fish, to have it turn round and fasten upon the hand. However, it is quite harmless, and those who are accustomed to them will have half-a-dozen hanging on their hand at a time, and take no notice of them.
Alreadyhas it been mentioned that Surgery has pressed into its service the weight of the atmosphere by means of cupping. She also makes use of Nature in a similar manner by employing the Leech for local and surface bleeding.
The mouth of the Medicinal Leech forms an exact parallel with the cupping-glass and lancets, only that it is very far superior in its powers. To make the analogy perfect, the lancets ought to be within the cupping-glass, and the latter ought to be able to exhaust the air from itself, and to be attached to a reservoir into which the blood could be passed.
I need hardly mention that the action of sucking as practised by the young of all mammalian beings, from man downwards,is due to the same principle. By the action of sucking a partial vacuum is formed, and the pressure of the atmosphere upon the breasts forces the milk into the mouth of the young.
We might multiply examplesad infinitum, and we will therefore pass to another subject.
Image unavailable: ICHNEUMON-FLY. GRASSHOPPER. SEED-DRILL.ICHNEUMON-FLY. GRASSHOPPER. SEED-DRILL.
Among the modern improvements in agriculture we may reckon the invention of the Seed-drill as one of the most important. By means of this invention, seed is greatly economized, the supply can be regulated, and the sower knows exactly where every grain of seed goes. There is no scattering, as in the wasteful broadcast plan, by which the seeds are flung almost at random over the field, and may or may not fall into the furrows. The Seed-drill, on the contrary, either stamps holes or ploughs narrow furrows, measures the seed into them, and in some machines replaces the earth. The former kind of machine rather deserves the name of a dibble, and was invented for the purpose of superseding the use of the hand-dibble.
It is really a pitiful thing to see human beings endowed with reason and aspirations performing such a task as dibbling by hand, one going backwards with a dibble in each hand, and the other following and putting seed into the holes. Yet the field labourers have the greatest objection to the machine dibble, as, indeed, they have to any sort of labour-saving machine, thinking that it will lessen the demand for labour, and prevent them from earning a livelihood.
I well remember how a country clergyman, pitying the hard toil of the hand-dibblers, took occasion when he visited town to purchase a machine dibble wherewith one man could set eight rows of beans at once. It was a very simple affair, comprehensible even by the dull brain of a Wiltshire labourer. His trouble was all in vain, for no one would use it, and there was such a disturbance about it in the village, that for the sake of peace its owner laid it up in a loft and abandoned its use. There might be some semblance of reason in thinking that it would deprive them of their field labour, but no cottager would even use it in his own garden, though it was freely offered to any one who wished to borrow it.
Thesemachines have their parallels in Nature, two of which are represented in the illustration.
The lower left-hand figure represents the female Grasshopper depositing her eggs. She is furnished with a sharply pointed ovipositor, composed of two blades. When she is about to lay her eggs, she searches for a suitable piece of ground, where the earth is tolerably soft, and with the closed ovipositor bores a hole. She then separates the blades slightly, and an egg glides between them into the ground, precisely as is done by the machine dibble with its beans. When I first saw and used the instrument, some twenty-five years ago, the parallel struck me at once.
Thefemale of the familiar Daddy Long-legs (Tipula) acts in a similar manner. She is furnished with an ovipositor too short to be used like that of the grasshopper, and so she attains her object in a rather different manner. Making use of her long stilt-like legs, she sets herself nearly upright, with the point of the ovipositor in the ground. She then twists herselffrom side to side, just after the principle of the bradawl, and so proceeds until she has made a hole large enough for her purpose. The blades of the ovipositor are then separated, and the egg placed in the hole, as has been described of the grasshopper.
Theupper figure represents one of the large Ichneumon-flies depositing the egg in the grub of some wood-inhabiting larva. How she bores the hole has already been described when treating of Boring Tools, and the process need not again be discussed. The principal point at present is, that after the hole is bored, an egg can pass between the blades of the ovipositor, though they are but little thicker than human hairs.
One of the most extraordinary instances of this kind of ovipositor is found in an Ichneumon-fly brought from Bogotá. The body, from the head to the end of the tail, is not quite an inch long, while the ovipositor is six inches and a half in length, and scarcely thicker than that of the insect whose portrait is given in the illustration. Nothing is as yet known of its habits, so that the object of this wonderfully long ovipositor is a mystery. But that it should be used like other ovipositors is evident enough, and the chief wonder is, what are the mechanical means whereby an egg can be propelled between blades so long and slender.
There is a genus of Ichneumon-flies called Pelecinus. They deposit their eggs in wood-boring larvæ, and we might imagine that the ovipositor would be a long one. It is, however, extremely short, and the requisite length is obtained by the form of the abdomen, the joints of which are so long and narrow that they almost look as if they had passed through a wire-drawing machine, the length of the head and throat being three-eighths of an inch, and that of the abdomen an inch and a half. This long abdomen belongs only to the female, that of the male being short and club-shaped.
The Teazle and its Structure.—Its Use in raising the “Nap” on Cloth.—Its Value in Commerce.—Artificial Teazles.—The modern Cloth-dressing Machine.—The Brush an Article of Luxury.—Definition of the Brush, and its various Uses.—Brushes in Nature.—The Foot of the Fly and the Tail-brush of the Glow-worm Larva.—Mode in which they are used.—The Comb.—Varieties of the Comb as made in different Countries.—Combs in Nature.—Foot of the Spider and its Uses.—Beak of the Toucan.—Comb of the Scorpion.—Buttons, Hooks and Eyes.—Use of the Button.—The Egyptian Garment.—The Buckle and the Shoe-tie.—The Clasp.—Wing-hooks of various Insects.—The Saddle-back Oyster.
The Teazle and its Structure.—Its Use in raising the “Nap” on Cloth.—Its Value in Commerce.—Artificial Teazles.—The modern Cloth-dressing Machine.—The Brush an Article of Luxury.—Definition of the Brush, and its various Uses.—Brushes in Nature.—The Foot of the Fly and the Tail-brush of the Glow-worm Larva.—Mode in which they are used.—The Comb.—Varieties of the Comb as made in different Countries.—Combs in Nature.—Foot of the Spider and its Uses.—Beak of the Toucan.—Comb of the Scorpion.—Buttons, Hooks and Eyes.—Use of the Button.—The Egyptian Garment.—The Buckle and the Shoe-tie.—The Clasp.—Wing-hooks of various Insects.—The Saddle-back Oyster.
IN former days, when so much was done by hand that is now done by machinery, the thistle called the Teazle (Dipsacus fullonum) was of great value in British commerce, being used by countless thousands in the manufacture of broadcloth.
When the woollen threads are woven so as to form the fabric of the cloth, there is no nap upon them, this having to be produced by a subsequent process. The plan of former days was, to procure a quantity of the seed-vessels of the Teazle, and dry them. They were then fastened to an instrument something like a wooden battledore, and swept over the surface of the cloth. By degrees the delicate hooklets which terminate the many scales of the seed-vessel tore up the fibres of the cloth, and produced the desired nap without impairing the strength of the thread. When this nap is worn off, the threads are again visible, producing the effect called “threadbare.”
As the art of weaving continued to progress, the demand for Teazles increased in due proportion, and vast quantities wereimported from abroad. Instead of being used by band, they were then fastened to the circumference of wooden wheels as broad as the width of the cloth, and made to revolve rapidly, while the cloth was pressed against them.
Image unavailable: TEAZLE. CLOTH-DRESSING.TEAZLE. CLOTH-DRESSING.
For many years attempts had been made to construct artificial Teazles which would not wear out so rapidly as did the dry seed-vessels, but nothing could be constructed that was not too stiff or too strong, and which did not injure the threads while producing the nap. At last, however, this difficult problem has been solved, and the Teazle is no longer an important article of commerce, its place being supplied by delicately made cards of the finest and most elastic wire.
In the illustration a head of Teazle is given on the left hand, and on the right is seen the mode in which the wire cards are placed in the machine, and the cloth drawn over them so as to produce the required nap.
Itis worthy of notice that there are many articles of comparative luxury which could not be used until man had attained some degree of civilisation. Among these we may class the Brush and the Comb, no true savage ever troubling himself about either article. The Brush, indeed, belongs to a much more advanced stage of civilisation than the Comb, for whereas we find combs, however rude they may be, used in semi-savage, or rather, barbarian countries, the Brush is, as far as I know, an adjunct of a high state of civilisation.
Brushes may be defined to be instruments formed of fibres set more or less parallel to each other. The vast variety of brushes used in different parts of Europe is indicative of the civilisation of the nations who use them. Take, for example, the brushes used in household management, such as the hearth-brush, the housemaid’s brush, the Turk’s-head brush, the crumb-brush, the stair-brush, the carpet-brush, the dusting brush, and many others.
Then we have those which are applied to our garments, such as the ordinary clothes-brush, the velvet-backed hat-brush, and the three kinds of boot-brushes.
In architecture, again, we should be very badly off without the painting-brushes, the whitewasher’s brush, and the paper-hanger’s brush; not to mention the exceeding variety of brushes used by artists both in oil and water colours.
As to brushes applied to our persons, we have an infinite number of them. There is, of course, the hair-brush, without a pair of which, one for each hand, no one with a respectable head of hair could be expected to be happy.
We may add to this the revolving brush worked by machinery, which is to be found in the rooms of any respectable hairdresser, and which is a sort of an apotheosis of the Hair-brush, especially when it is worked, as in some places, by the electrical engine.
Then there is the shaving-brush, once an absolutely necessary article in a gentleman’s dressing-case, and above all requisite if the owner should happen to be a clergyman. Nowadays, shaving is rapidly decreasing, and of all the professions, those who are most largely bearded, both in number of beard-wearers and dimensions of the beard, are to be found among the clergy.
Then there are any number of tooth-brushes for the interior of the mouth, and of flesh-brushes, with or without handles, for the service of the bath. There are even gardeners’ brushes, for the purpose of clearing the plants of the aphides, or green-blight, as these insects are popularly called by gardeners. So it will be seen that—absurd as the proposition may appear at first sight—we may really accept the use of the brush as a safe test of the progress of civilisation.
Wewill now glance at the illustrations of this subject.
On the right hand is depicted the once honoured Shaving-brush, the terror of all stiff-bearded men on frosty mornings, and yet clung to with a strange inconsistency. Many years ago a military member of the House of Commons was sensible enough to wear his beard, and was, in consequence, the butt for interminable jokes. At the present time, if the House were counted, a great majority of the younger, and not a few of the older, members will be found to wear either the beard or moustache, or both.
Image unavailable: FOOT OF FLY. BRUSH OF GLOW-WORM LARVA. HAIR-BRUSHES. SHAVING-BRUSH.FOOT OF FLY. BRUSH OF GLOW-WORM LARVA. HAIR-BRUSHES. SHAVING-BRUSH.
Perhaps some of my readers may object that many nations in a state of very partial civilisation are accustomed to shaving. So they are, but they do not use the shaving-brush. Most of them content themselves with pulling out the hairs by the roots, while others merely saturate the hair with hot water, and so need no brush.
Next to the shaving-brush is drawn a pair of ordinary Hair-brushes, such as have been mentioned.
Passingto the left, we find an object which bears a curious resemblance to the shaving-brush. This is an apparatus belonging to the larva or grub of the Glow-worm. This creature feeds upon snails, and, in consequence, gets itself covered with the tenacious slime. In order to enable it to rid itself of this inconvenience, the larva is furnished near the end of its tail with the curious apparatus which is here shown. It consists of some seven or eight soft white radii, arranged so as to produce a brush-like outline, and being capable of extension or withdrawal at will.
It had long been known that this “houppe nerveuse,” as it is called, was employed as an assistant in locomotion; but until comparatively late years—I believe about 1826—no one seemed to be aware that it was used as a brush. Its functions as a brush may be compared with the somewhat similar offices fulfilled by the pincers of the Earwig, as mentioned on page259.
Next to the brush of the glow-worm larva is shown one of the fore-feet of the ordinary house-fly, much magnified. Passing, as irrelevant to the present subject, the use of the feet as organs of locomotion, we may take them as being used for the purpose of cleansing the body of the insect.
I suppose that none of my readers has been sufficiently inobservant not to have noticed the way in which a fly cleanses itself, behaving almost exactly like a cat under similar circumstances. The fore-feet are repeatedly passed over the head, which is bowed down to meet them, while a similar office is performed for the rest of the body by the hind-legs. The feet are then rubbed against each other, so as to free them from all accumulations, just as the housemaid cleanses the hair-brush with the comb before washing it. So mechanical is this process, that a fly has been known to go through it even after it had been deprived of its head.
The reader will see, on reference to the illustration, that the two sharp and curved claws are capable of answering the purpose of combs, and, indeed, are so employed.
Wewill now proceed to theComb, and see how Art has been anticipated by Nature.
As long as human beings possess hair upon their heads, whether it be the short, frizzed, woolly pile of the negro, the thick, coarse crop of the Fijian, the coarse, straight hair of the Mongolian, or the long and fine hair of the Georgian races, they must, as soon as they attempt any kind of civilisation, form some instruments by which the hair can be dressed. The simplest machine for this purpose is the Comb, and I possess many varieties of this article, suitable to the different races for whom it was made.
Putting aside the ordinary Combs of our European civilisation, such as are given in the illustration, there are many others which are modified according to the use which they have to fulfil.
Image unavailable: FOOT OF SPIDER. BEAK OF TOUCAN. COMBS.FOOT OF SPIDER. BEAK OF TOUCAN. COMBS.
The simplest is the Comb of the celebrated Amazon regiment of Dahomey. This is nothing but a slight skewer of ivory, some ten inches in length, and amply sufficient for arranging the short woolly lumps which do duty for hair on the head of a true negro. One of these very primitive combs is in my collection, together with an undress costume of the Amazon in question, and both being very much suited to each other. The comb being a simple skewer, the dress is only a few thongs of leather, but they are both equal to the requirements of their wearers.
As much time would be lost in combing the hair with a single skewer, especially when that hair belonged to any but the pure negro races, a simple but obvious improvement was introduced. A number of skewers were lashed together side by side, with their ends a little diverging, and thus was formed the germ of our present Combs.
As to the varieties of the Comb, they are simply endless; and whether they are intended, in the form of the Currycomb, to smooth the harsh coat of a horse, or, as a small-tooth Comb, to search the hair of the young, they are all based on one principle.
It is really curious to see how often two men, who cannotpossibly have seen each other, will hit upon the same idea, not only simultaneously, but often in the very same words. So it is with regard to the Comb. In no two parts of the world can the natives be more opposed to each other than is the case with Fiji and Western Africa; yet I possess specimens of combs from both countries, made on the same principles, and so exactly in the same manner, that, except for the coarseness of the African Comb, it would be almost impossible to distinguish between them. There is but a slight difference in the size and shape of the two combs, and yet nothing can be more distinct than the characters of the two nations.
I have also a Japanese Comb of the most ingenious construction. It is made of wood, and cut exactly like our double ivory small-tooth comb; but it is furnished with a curious kind of handle, consisting of a flat piece of wood with a deep longitudinal slit, into which either side of the comb fits; and so beautifully is it made, that when it is fitted upon either side of the comb it looks as if handle and comb had been cut out of the same piece of wood.
The Fijian Combs are much after the same fashion as those of Western Africa, except that, with the artistic nature of their kind, the Fijians, instead of merely lashing together the numerous spikes of which the comb is made, employ a variety of patterns, and seem to luxuriate in the exuberance of artistic spirit which can make hundreds of combs, and no two of them alike.
Onthe left hand of the illustration are two examples of Natural Combs which are well worthy of notice. The upper one is a foot of the common Garden Spider (Epeira diadema), which has been several times mentioned in this work in connection with different subjects.
Every one who has watched the life of one of these creatures must have noticed how often its hairy body becomes clogged with little bits of its own web, and how dexterously it releases itself from such encumbrances. The figure in the illustration shows how this can be done, the strangely formed foot acting at the same time the part of comb and brush. It will be seen that the curved spikes of the claws act as a comb, while the bristle-like hairs discharge the duty of a brush.
Notonly are these projections used as Combs, but as appendages which insure the security of footing along the lines of the web. The reader will easily remember that when a Spider rushes along its web to secure its prey, it always runs along one of the radiating lines, which have no viscid drops, and that it never misses its hold. The latter point is secured by the structure of its claws, which are so made that if one projection misses the line, another is sure to fasten upon it. Some years ago, while watching “Blondin” go through his wonderful performances, I was especially struck with the pattern on which he had constructed the stilts upon which he traversed the rope. They were made in the most exact imitation of the Spider’s foot, and though it is not probable that he borrowed them from that object, the resemblance was so close that he might readily have done so.
Belowthe spider’s foot is given the head of a Toucan, one of those beautifully coloured and large-billed birds that inhabit tropical America. These birds are very particular about their plumage, and even when in captivity dress their feathers with the utmost care. When they do so, the saw-like notches of the beak act the part of a comb, and the fibrils of the feathers are by their action dressed parallel to each other, and give to the whole bird its proper appearance of health.
I mayhere mention that there is one comb in Nature, the use of which has never been clearly ascertained. This is the remarkable organ found in the Scorpion, and simply known as the “comb.” There are two of them, one on each side of the under surface. Their colour differs slightly according to the species, but is generally a light yellow brown. The number of teeth also differs extremely, for in the Rock Scorpion there are only thirteen teeth, while in the Red Scorpion there are twenty-eight.
Havingnow treated of brushes and combs as articles belonging to the toilet, we will proceed to those which belong to the dress rather than the person. It is a curious fact that, asfar as is known, buttons and hooks belong only to advanced civilisation. The simplest garment is, of course, a cloth of some material wrapped round the waist, and, as we see in the wonderful Egyptian paintings which have survived their painters some three thousand years, the simple fold can retain its grasp round the loins, even through the exertions of a long day’s work.
I was always at a loss, when looking at these drawings, to understand how a single fold could retain so simple a garment in its place, but when I made my first visit to the Hammam Turkish Bath in Jermyn Street the mystery was at once solved. The “check,” as it is there called, is long enough to pass about once and a half round the waist of an ordinary man. One end of it is placed on the left side, so as to bring the lower edge on a level with the knee. It is held by the left hand until the right hand passes it round the waist. It is then turned over in a broad single fold, and will remain in position for hours, the left leg having free scope between the two ends, and yet not being needlessly exposed.
Next to the simple fold comes the tie, which is in use all over the world. The chief object of a good Tie is that it should retain its hold as long as needed, be loosened with a touch in necessity, and, as a matter of consequence, should never “jam.”
Still, even the best of ties are liable to objection. I once heard an argument on the subject of ties and buckles with regard to shoes. The speakers were both Derbyshire men, and their phraseology was somewhat obscure. However, both stuck to his own principles, one saying that “when a shee-uew is boo-oo-oockled, it’s boo-oo-ookled;” and the other asserting, in equally strong terms, that “when it’s tee-ee-eed, it’s tee-ee-eed.”
The buckle was here asserting its supremacy in civilisation over the tie, and was palpably right. Any one, so rose the argument, can tie two strings together, but the structure of the buckle is too complicated to be understood, much less invented, by any uncivilised being.
Nextcome, in natural order, the Button and the Clasp, each being identical in principle. In the case of the formerthe “eye” is placed over the button, while in the latter the clasp or hook is passed through the eye. Several examples of the Button and the Clasp are given on the right hand of the illustration, and are too familiar to need description.
Asto the corresponding articles in Nature, they are very numerous. We will take, for example, the Saddle-back or Crow Oyster of our own shores. It is a most remarkable being. It deposits upon the object to which it adheres a sort of button of shelly matter, and the lower valve, which is nearly flat, has in it an aperture which is placed over the knob, just as a button-hole goes over the button. As this arrangement is confined to the lower valve, and cannot be seen unless the upper valve be removed, the lower valve only is shown in the illustration, as it appears when fastened to the side of a large limpet.
Image unavailable: WING-HOOKS OF INSECT. SADDLE-BACK OYSTER. CLASPS AND BUTTON.WING-HOOKS OF INSECT. SADDLE-BACK OYSTER. CLASPS AND BUTTON.
Ofthe Hooks and Eyes in Nature I have only taken two examples, though there are many others.
We all know the Bees, Wasps, Hornets, and other similar insects, and that they possess four wings. I may here mention that no insect which does not possess four transparent wings is capable of stinging.
When the insect is at rest the four wings may be easily distinguished, but when it is in flight they coalesce, so that practically the insect has two wings instead of four. This object is attained in the following way:—
The lower edge of the first pair of wings is turned over in a rather stiff fold. The upper edge of the second pair of wings has a row of small, but strong and elastic hooks. When the insect is about to fly, the hooks are hitched into the fold, and so the wings are fastened together. These hooks are shown in the illustration, and the reader will easily see how effective they must be in their operation. An almost exactly similar structure is found in the feathers of birds, and it is by means of these tiny hooks that wings are enabled to present a continuous, light, and elastic surface in the air.
Vessels and their Covers.—Corks.—Mode of bottling Wine.—Conical Corks and Stoppers.—Self-fitting Candles.—Candle-fixers.—The Vent-peg.—The Blow-guns and their Missiles.—The Serpula and its Conical Stopper.—The Filter.—The Bosjesman procuring Water.—How to make a simple Filter.—The Earth as a Filter.—The Sea-mouse, or Aphrodite, and its filtering Apparatus.—The Duck’s Beak, and its beautiful Structure.—The Jaw of the Greenland Whale.—Fork-grinder’s Respirator.—How Insects breathe.—Spiracles, and their general Structure.—Spiracle of the Fly.—Experiment upon a Cockroach, and its Result.
Vessels and their Covers.—Corks.—Mode of bottling Wine.—Conical Corks and Stoppers.—Self-fitting Candles.—Candle-fixers.—The Vent-peg.—The Blow-guns and their Missiles.—The Serpula and its Conical Stopper.—The Filter.—The Bosjesman procuring Water.—How to make a simple Filter.—The Earth as a Filter.—The Sea-mouse, or Aphrodite, and its filtering Apparatus.—The Duck’s Beak, and its beautiful Structure.—The Jaw of the Greenland Whale.—Fork-grinder’s Respirator.—How Insects breathe.—Spiracles, and their general Structure.—Spiracle of the Fly.—Experiment upon a Cockroach, and its Result.
THIS object, as depicted in the illustration, is a product of civilised life, though, as soon as a savage could make a vessel, he seems to have made a Cover for it if it were of large diameter, or a Stopper if the opening were small. Even the very Bosjesman, who is quite unable to make a clay vessel, and uses empty ostrich eggs by way of water-bottles, is yet capable of making plugs with which he can stop up the apertures. Then the Kafir, with his gourd vessels, whether they be for water or snuff, makes a plug that fits tightly enough to exclude the air, as well as to retain the contents.
The invention of glass bottles necessarily brought with it the introduction of a new kind of plug, and a material for such a plug was found in the bark of the cork-tree, a species of oak. This bark possesses the capability of compression to a very great extent, and, being highly elastic, it expands as soon as the pressure is removed.
Thus, in bottling wine, the corks are always made much too large to go into the mouths of the bottles. They are firstdipped in a cup containing the same wine, and are then compressed violently by a machine worked by a handle, and which, being practically a powerful pair of nut-crackers with a rounded gripe, must suit the shape of the cork. It is then taken out of the machine, and, before it has had time to expand, is rapidly fitted to the neck of the bottle, and driven home with a wooden mallet. Expansion then takes place, and the bottle is rendered air-tight, so that no damage is done to the wine.
If the whole of the wine were to be drunk when the cork was removed, this plan would be amply sufficient. But there are many cases where the bottle is opened, and only part of the wine consumed. To re-cork the bottle would be too troublesome, and to leave it uncorked would spoil the wine. So the Conical Stopper was invented, which fits the neck of any ordinary wine-bottle, according to the depth to which it is introduced, and, by a slight screwing movement, sufficient compression is obtained to render the bottle air-tight. One of these Conical Stoppers is shown in the illustration onpage 352. Sometimes they are made of cork, and sometimes of india-rubber; but the principle is the same in either case.
Perhaps some of my readers may have seen the Self-fitting Candles, which require no paper to make them fit the candlestick. These are enlarged at the base, which is made in a conical form, and slightly grooved. The “Candle-fixers” that are so much in use at the present day are made exactly on the same principle, being hollow cones of paper, which take the place of the solid cone.
The Vent-peg of casks is another instance of the cone used as a stopper.
Another example is to be found in the Blow-guns and Arrows of tropical America. In some districts the base of the arrow is fitted with a conical appendage of light cotton, rather larger than the tube, but capable of compression, so that it exactly fits the tube when pressed into it. In other districts the cone is hollow, and made of some thin and elastic bark.
Some years ago one of our most eminent gun-makers hit upon the same idea while making improved missiles for the game of “Puff and Dart,” and very much surprised he was when I showed him the South American arrow, not only with the same hollow cone at the base, but having also spiralwings along the shaft, so as to give it a rotatory motion as it passed through the air. The hollow cones of his darts were made of india-rubber, but the shape of the two was identical.
Ifthe reader will refer to the left-hand figure of the illustration, he will see a beautiful example of the Conical Stopper as existing in Nature.
This is the “Stopper,” as it is popularly called, and, scientifically, the “infundibuliform operculum.” I prefer the former term myself, as being less liable to misapprehension.
The Serpula lives in a shelly tube of its own construction, and has the power of protruding itself when it desires to obtain food, and of withdrawing itself within the tube when alarmed. This movement is performed so rapidly, that the eye can scarcely follow it, and the mechanism by which it is done has already been described when treating of War and Hunting.
Image unavailable: ANTENNA OF SERPULA. CONICAL STOPPER.ANTENNA OF SERPULA. CONICAL STOPPER.
When it withdraws itself, the Stopper closes the mouth of the tube with perfect exactness, so as to leave the inhabitant in safety. The reader will see, on referring to the illustration, how exactly similar is the Conical Stopper of Art to that of Nature, and how the inventor of that article, as well as of the self-fitting candle, the candle-fixer, the blow-gun arrow, and the vent-peg, might have found prototypes of their inventions in Nature, if they had only known where to look for them.
Evenin a state of uncivilisation man has been driven to invent a Filter of some kind.
The simplest kind of Filter is that which is used by theBosjesman women when procuring water for the use of their families. When, as often happens, the only water to be obtained is to be found in muddy pools which have been trampled and perturbed by thirsty animals, the women have recourse to a simple, though rather repulsive, expedient.
Each woman is furnished with empty ostrich egg-shells by way of water-vessels, and she also takes a couple of hollow reeds. Over the end of one of these reeds she ties a bundle of grass, and then plunges it as deeply as she can into the mud. After a little while she sucks up the water through the tube, the grass acting as a filter, and she then discharges it by the second tube into the egg-shells. In this way the women will obtain water, where none but themselves could have procured it. As to the repulsive mode of obtaining it, no one can be fastidious when dying of thirst. Sir S. Baker mentions that when he was on his travels he managed in a halt to save up enough water for a bath for himself and his wife. He was about to throw away the soapy water, when the vessel was snatched from his hands by two of his attendants, and the contents eagerly drunk.
The different varieties of the Filter which we use at the present day are too familiar to need description. Whether they be made principally of charcoal, which is a powerful disinfectant, or of merely stones, gravel, and sand, they are all constructed on the same principle, namely, the straining out solid substances, and allowing only the pure water to pass through the interstices.
Asto the Filters of Nature, they are almost innumerable. In the first place, the Earth itself is the primary filter of all, taking into itself all kinds of decomposing substances, separating them for the use of vegetation, and delivering the pure, bright, and sparkling spring water which we so highly and rightly value. The whole human body, again, is practically a collection of the most elaborate and effective filters that the mind of man can conceive. But we will pass to the more obvious examples of filters as seen in animal life.
On the upper left-hand portion of the illustration may be seen a long, fat, hairy creature, called popularly the Sea-mouse, and known to zoologists asAphrodite aculeata. Although it inhabits the mud—and sea-mud is about asnoisome a substance as can be imagined—it is clothed with a garment of such beauty that the rainbow itself can scarcely rival, and not surpass it. The hairs with which it is so profusely covered glitter and sparkle with every imaginable hue, among which red and green seem to be predominant.
These hairs occupy the sides of the body, but in the upper surface there is a thick coating of felted hairs, interwoven with each other so closely that they can with difficulty be separated. These hairs form a natural filter, strain away the mud from the water, and allow the latter to pour itself upon the organs of respiration. If, therefore, a specimen be examined when it is first brought up by the dredge, the felted hair will always be found to contain a considerable amount of mud, and much washing is needed before the creature can be introduced into an aquarium where the water is intended to be transparent.