Fig. 40. Scratch-brush Lathe.
The finishing of silver work requires some little knowledge and skill to perform it properly; and we think that a few observations bearing upon it will be of service to those for whom this manual is written. After either of the processes of whitening or plating, the work has to be scratched, unless required to be left adeadwhite, then this process does not take place; the scratching removes from the surface the dull white colour produced by the above processes, and effects a characteristic bright and uniform colour to the work of the silversmith. Scratching is done at the lathe (Fig. 40) by the application of a very fine brass-wire brush of circular form running upon the spindle; a solution of weak ale runs from a barrel with a tap to it, placed upon the framework of the lathe so as to enable the beer running from it to fall upon the brush during the whole time of its rotary action, and this assists the brush the more easily to glide over the surface of the work submitted to it. A large quantity of silversmith’s work receives no other treatment than this, after the whitening processes have taken place. Silver chains are burnished by means of a polished steeljack chain, and the application of a little soft soap and hot water, or otherwise scratch-brushed. The beautiful frosted surfaces to be seen upon silver lockets, and other work of a similar nature, are all produced by means of the scratch-brush.
Burnishing is another mode of finishing silver work. It produces a polished surface, which reflects like a mirror, and gives the greatest lustre: it removes marks left by the polishing mixtures, and produces a darker surface than the other modes of finishing. The tools employed for this process are extremely variable, and well adapted to the different kinds of work to which they are applied; they are of two kinds, one being formed of hard stone, and the other of polished hardened steel; they vary with regard to shape, some being straight with rounded points, or with curved and blunted edges, others with large rounded surfaces, &c. Stone burnishers are made of blood-stone, which is mounted in a wooden handle with a brass ferrule, which firmly secures the stone to it, in which state it is used. Steel burnishers are likewise fixed in wooden handles, which enable them to be firmly grasped by the operator. Throughout the whole process of burnishing, the tool should be repeatedly moistened with a solution of soap and water; which causes itto glide more easily over the surface of the work, prevents it from becoming too much heated, and generally facilitates its action. In consequence of the great friction which the burnishing tool undergoes, it soon loses its bite, when it slips over the work as if it were greasy; its effectiveness must therefore be restored from time to time by rubbing it upon the leather which the workman has beside him for the purpose. It generally consists of a piece of buff leather, impregnated with a little crocus. In very small articles only steel burnishers are used, as they are finer in make, and by their greater variety of form, are exceedingly well adapted to all kinds of work; in this class of work, if any soap-suds should adhere to the article they may be removed by the application of a little tissue paper. Large pieces of work are rubbed with a piece of old linen, or washed in a warm solution of soap and water, rinsed, and dried in boxwood sawdust, which finally completes the process.
Silver work may be oxidized by any of the following processes:—
Reduce the above ingredients to a fine powder,and dissolve it in a little acetic acid. If the article is to be entirely oxidized, it may be dipped for a short time into the boiling mixture; if only in parts, it may be applied with a camel-hair pencil, the article and the mixture both being warmed before using.
Dissolve the platinum in the mixture of acid, evaporate to crystallization, and when cold, dissolve again in a little sulphuric ether. Apply the mixture with a camel-hair pencil to the parts required to be blackened.
Reduce the salts to powder, and place it in a black-lead crucible along with the acid, boil up, and then dip the articles into the mixture for a short time, or otherwise apply it to the parts required to be oxidized.
These mixtures will give the various tints of oxidation to silver work if properly treated; but if other tints be desired, the following chemical substancesmay be employed according to taste:—For slate-coloured surface, dip the articles into a boiling solution of sulphuret of potassium. Strong hydrosulphate of ammonia produces a dark tint of oxidation, and if diluted with much water a light tint is produced. Nitric acid produces a light surface. The fumes of sulphur produce a beautiful blue-coloured surface. This operation should be conducted in a closed box, and all parts not to be blackened should be coated with a suitable resist varnish. After any of these processes the articles may either be scratched, or otherwise burnished.
CHAPTER XI.
Imitation Silver Alloys.
The undermentioned white alloys have their various uses in the industrial and mechanical arts, some being employed as common silver, whilst others are manufactured as near as possible in imitation of it, and used as a substitute, for many purposes. In melting the alloys in which nickel and several other compounds enter into combination, unless very great care be exercised, it is a difficult matter to maintain the true and definite proportion of each metal of which the alloy proper is composed, owing to the loss of the more fusible metals by volatilization, if allowed to remain too long in the furnace. The best method of preparing the compound for the crucible, is to mix the copper and nickel together. The latter is produced from the pure oxide of nickel; therefore it is taken in this form and placed in the crucible with the copper at the commencement of the operation. Whenthese ingredients are well melted, and incorporated by stirring, add the zinc or other fusible metal required to make up the compound, previously heating it thoroughly over the mouth of thecrucible, to prevent the chilling of the already molten metal which it contains. When silver forms a component part in any of these alloys it should be added at the beginning of the process along with those of a high degree of fusibility, and reduced under the protection of a suitable flux; charcoal being the best for the purpose. This flux also tends to preserve the fusible metals, upon their addition to the melted compound in the pot, from too suddenly flying away in the shape of fumes. The best zinc of commerce should be employed in these alloys, which is sold under the name of spelter.
Common silver alloy alloy—
Another—
Common silver alloy—
Another—
Another—
Another—
Common silver alloy—
Another—
Another—
Another—
Common silver alloy—
Another—
Chinese silver—
Imitation silver—
Imitation silver—
Another—
Another—
Another—
White alloy—
Clark’s patent alloy—
White alloy—
Alloy with platinum—
Alloy with palladium—
The platinum and palladium of which the last two alloys are composed, although very difficult to use in combination with any other metal, readily unite in any proportions with silver; and it has been found that such alloys are not so easily tarnished as the ordinary ones, or even as fine silver itself. These various alloys serve to effect the several purposes for which they are employed in manufactures; wires prepared from any of them will supply the place of silver, as brooch tongs, stems for pins, catches and joints, &c. for articles of common quality and cheap workmanship. They are also employed for preparing the ground for “electro-plate,” for which they are very serviceable. When, however, these alloys are employed by the regular silversmith, care should be taken not to get the scraps of metal in any way mixed with those of the better material, otherwise difficulties will soon begin to present themselves, which will materially interfere with the regular and proper working of the best silver alloys; and in fact, with all qualities that have originally beenprepared free from nickel. Those prepared from nickel are much more infusible than those made without it; consequently, if a piece of the nickel alloy, either by accident or design, gets intermixed with the other quality, in a subsequent melting, it will be found to float upon the surface of the molten metal for some considerable time, and thus retard the process. Alloys prepared in imitation of silver are harder and much more difficult to work than those of the true metal; therefore it can easily be imagined what alteration the latter undergo upon the addition of some of the former compounds. The hardness and toughness which these alloys possess admirably adapt them for such purposes as we have described.
CHAPTER XII.
Economical Processes.
In all silversmiths' establishments, the economical or waste-saving processes, as they are termed, require special and careful attention, so that the actual working loss, or that portion of it which is entirely irrecoverable by the manufacturer, may be reduced to the lowest possible degree. It may not be known to the general reader, or to the beginner in the precious metal trades, that there always takes place in the working up of the metal a loss of material, a portion of which the manufacturer is unable to recover, however cautious may be the means employed for that purpose. In the best regulated workshops, this loss will amount at the lowest estimate to about 2½ per cent. of the whole quantity worked up in the establishment. If the actual loss can be reduced to within the above limit it is considered very low, and highly satisfactory. Taking into considerationthe loss that is occasioned in precious metal working, and from calculations that we have made from experience, we have long since arrived at the conclusion, that it cannot possibly be estimated under 10 per cent. of the total work daily performed; and this opinion is based upon experiments, therawmaterial being weighed before the process of melting and after the articles were completed, a fair calculation of course being made for unfinished work. This was including every description of manufacture; in some branches of the trade the working loss is not quite so great, but then there are others in which it is exceedingly heavy, so that the estimated loss in the jewellery trades cannot be safely put at a lower percentage than we have quoted.
It will thus be seen that therealloss, such as manufacturers are unable to recover by the means already known to them, amounts to one-fourth part of the total working loss of the establishment. This is easily accounted for: in the first place, a little takes place in the melting of the various alloys, the re-melting of scrap metal, the reduction of lemel, &c.; then there are the sundry manipulations of working; the passage of the metal through various acids, and the processes of finishing, each of which detaches small particles ofmetal, too small to be visible to the naked eye, but all of which go to form a portion of the loss which the manufacturer never recovers. The unrecovered metal may be judiciously proportioned as follows:—A portion of it works itself into the wood-work of the flooring of the shops, lathes, boards, and other parts of workshop appliances; then there is the refiner’s profit—as purchases of the sweep, polishings, and other refuse of precious metal workers. Instances can be recorded in which shrewd business-men have actually taken up the floors of their workshops and recovered a vast quantity of metal which was supposed to be lost for ever; and instances are well remembered in which two jewellers, upon removing into more extensive premises, availed themselves of the opportunity, not only of removing the boards which formed the flooring of the premises they were about to leave, but also those of the tenants they were about to succeed. In one case, metal of the value of £80 was recovered, and in the other it reached the large amount of £150. The two jewellers referred to, of course, were too un-English to refund the proceeds to the late tenants, who, when they became aware of it, if ever they did, would be, no doubt, wiser if sadder men.
To prevent the precious metal from finding itsway into such places as these, it is advisable to have the floors well protected with sheet zinc or iron, in which case not the least particle could be lost in this manner. The extra cost of laying the floors would soon be amply repaid, by an extra quantity of the working loss being recovered; and if other equally effective precautions were adopted in the waste-saving processes by precious metal workers, therealloss, which they cannot avoid suffering, might even yet be reduced to the lowest possible point. Iron or zinc covered floors may be protected from wear, by laying over the surface small square grates of perforated iron, and these, being removable, may be readily taken up at stated periods, for sweeping the refuse from the floors; once a month will be found often enough to do this. The gratings should, however, be swept over lightly every day in order to remove the dust and particles of metal that may accumulate upon the surface into the perforations, and also for the removal of waste paper and other rubbish, continually accumulating in workshops.
Floors containing no such waste-saving precautions, are commonly swept over once, and sometimes twice each day, the refuse arising therefrom being carefully passed through a very fine sieve, all extraneous matter removed, and theresidue remaining in the sieve being well sorted for the detection of all the precious metal visible to the naked eye. The whole refuse matter is then thoroughly burned in a muffle provided specially for the purpose, and finally reduced to a fine powder in a cast-iron mortar. When it has reached this stage of the process, it is quite ready for the particular kind of treatment it next receives at the hands of the refiner. Grinding by large stone rollers is now fast superseding this mode of pulverising jewellers' waste and refuse. When the latter plan is adopted, the refuse should be swept from the floors every morning, carefully looked through, and then transferred to a barrel (having the top removed, which may be used as a lid), where it can be well kept together, and hidden from view until the time arrives for its further treatment.
The waste which accumulates in the processes of polishing, lapping, &c., is greater than that already referred to, consequently, it cannot be too carefully looked after, in every stage, where a large manufacturing trade is being carried on in various branches. It is advisable in the practice of true economy, for the polishing, lapping, and scratching boxes to be repeatedly cleaned out, and the contents removed out of the temptation ofevery one, by being placed in a box, well lined with either sheet lead or zinc, which ensures the perfect safety of the material placed therein from all irregularities in the workshop. This kind of waste on being prepared for sale is again placed in a very strong wrought-iron box, made of a suitable size to fit the muffle, and having a thick close lid to it. After the work of the day has been completed, the fire in the furnace or muffle is made up, the dampers are closed, and then the iron box containing the refuse is at once passed in and allowed to remain there till morning, when every particle of matter will have become thoroughly burned; a slight pulverization after this process readily reduces it to a fine powder; further operations then cease, and the product is in all probability in a fine state of division, and fit for the subsequent operations of the refiner and assayer, whose special business it is to attend to these arrangements of precious metal workers.
The next process we have to consider is one which includes the whole of the liquid substances variously employed in silver-working establishments, such as the pickling solutions, washing-out waters, whitening mixtures, and waste or spent solutions of every kind. The whitening solutions or mixtures, when in use, should be kept apartfrom the ordinary cleansing liquids, as after they have been in use for a time, they become saturated with copper taken off the work during the whitening processes; if the solution is then set aside for some time the copper eventually crystallizes out from the liquor, which may be poured into the waste-water tub, and the remaining crystals of sulphate of copper, for such it then is, may be removed and preserved.
In small establishments one large tub, to form the receptacle for all spent or used-up liquids, will be found sufficient; but in large places several will be required. In the former case the water is only drawn off at the beginning of every fresh week, which allows plenty of time for the precipitation of the silver without any disturbance taking place in the mixture between the close of one week and the commencement of another; whereas in large concerns it requires to be drawn off continually unless other vessels are provided for its reception during a long period. Attempts have been made to recover the silver from these solutions by simply filtering the liquid through a coarse piece of felt or flannel; or by providing a false bottom in the tub or other vessel containing the waste waters, arranged in the following manner:—A tolerably large tub would be employed, being about one-fourthfilled with coarse deal sawdust, next would be placed the false bottom perforated with numerous small holes, and upon this would be firmly secured a piece of felt, so as to exactly fill up the space in that part of the tub, which then serves to act as the filterer of all solutions poured in above. The liquid after passing through the piece of felt proceeds through the perforations in the false bottom into the sawdust beneath, where it is allowed to run away by means of a small hole or tap at the bottom. But the use of either of these processes, if adopted on a large scale, where the waste products amounted to some hundreds per annum, would be wretchedly bad economy and tend to a serious loss of valuable metal; the boiling sulphuric acid, used in cleansing the work and for other purposes, has the power of dissolving minute particles of silver as well as those of the baser metal which always enters into the composition used in the production of the work of the silversmith; therefore, that portion of the metal which has become dissolved and entered into the chemical state, requires to be brought back to its original form before it can be saved by such means as those just described. To illustrate this more clearly, we will take the process of gold-colouring. If workmen were to notice the rinsing watersemployed in this process, subsequently allowing the vessels containing the rinsing to stand for a very short time, upon pouring away the surplus water, a white curdy precipitate will at once be observed at the bottom. This is the silver removed from the surface of the gold alloy, which has been precipitated by the muriatic acid and the common salt employed in the colouring mixture, into the form ofchloride of silver. Now in this proceeding there is no gold to be seen in any of the vessels, but it is a well-known fact that a portion has been removed during the process from the surface of the gold articles. Where is it? Why, it has become dissolved, and is therefore held invisible in the solution, in consequence of the colouring mixture forming the well-known solvent for gold,aqua-regia. This is exactly the case with a portion of silver in the silversmith’s solutions; small particles are continually being dissolved by the mixtures employed, and are thus held in solution past the power of filtering, unless some chemical ingredient be added to it, which acts as a re-agent upon the metal sought to be recovered. From what we have seen in the colour water, which always contains a little silver, it is evident that both muriatic acid and common salt will do this work for us. We prefer common salt, on accountof its cheapness, besides being easily procurable.
The best mode of treatment for the silversmith’s waste waters, after being collected together by pouring into the receptacle specially provided for that purpose, is to prepare a saline solution for the precipitation of the silver. This may be made by mixing together common salt and tepid water, in the following proportions:—
Common salt 3 oz.Tepid water 1 pt.
The water need only be sufficiently warm to dissolve the salt, and the proportions given do not require to be strictly adhered to; in fact any quantity, if properly mixed, will do to effect the purpose required, and we merely give these as a guide for the process. In small establishments where only one tub is employed, the above proportion of saline solution may be added (every Saturday after the completion of the day’s work) to the waste-water; the whole should then be stirred slowly in a circular direction, and allowed to settle until Monday morning, when all the surplus water may be drawn off and poured away. In larger establishments the accumulation of waste-water is greater, therefore several collecting vessels should be employed, and the mixture for precipitationmay be added to them at other times than those stated, if required, and in accordance with workshop regulations. The sediment produced in the collecting vessels after the supernatant water has all been drawn off, may be removed, dried by heat in a strong iron pan, and subsequently sold to the refiner.
CHAPTER XIII.
Licences and Duties.
Manufacturing silversmiths, and all persons trading in silver wares of more than five pennyweights each, are compelled to take out a licence; articles under that weight being exempt. The licence has to be taken out annually, and costs £2 6s.for manufacturing or trading in articles under thirty ounces in weight, and £5 15s.for articles of thirty ounces and upwards. It should be taken out on the 6th day of July in each year at the Excise Office. This Act of the Legislature was passed in the year 1803, 43 George III. c. 69, and is not the only one which refers to the subject we are now considering. There are other conditions besides the compulsoryPlate Licence, as it is called, to which manufacturing silversmiths are subject, such as the supervision of the assay offices, in the case of certain descriptions of goods; and the payment of duty on all such goods. At thepresent time all hall-marked silver articles have to pay a duty of 1s.6d.per ounce, calculated not on their gross weight, but on five-sixths of the weight, the other sixth being allowed for waste in finishing the articles, as they are sent to the Hall in a half-finished state. The duty is paid at the Assay Office at the time the goods are sent to be marked. Some dissatisfaction just now exists in a portion of the trade with regard to the above duty, as it is considered excessive, besides having a tendency to discourage the manufacture of silver wares; be this as it may with respect to a certain description of goods, on the bulk of the trade it can have no injurious effect whatever. The duty is paid only on manufacturedplateand such other articles as are requested to be hall-marked; besides which the trade in this particular department of manufacture has never been very extensive, being confined to a few firms of eminence only.
Before going into the general details of this question, it will be as well, perhaps, if we give a short history of the imposts that have existed in the silver trade for some time back. The first impost that we can find recorded took the shape of aduty, and was levied as far back as the year 1720, by 6 George I. c. 11, which placed a tax of 6d.per ounce on all silver plate manufactured inGreat Britain, which, should be assayed or marked. The officers of the Excise were to collect the tax, but the great difficulty of ascertaining the number of ounces worked up, which the provisions of the Act did not clearly set forth, soon rendered it ineffectual, and it was consequently repealed by the statute 31 George II. c. 32, and a licence then substituted had to be taken out by manufacturers and dealers in plate. The licence at this period amounted to forty shillings, and had to be renewed annually. In 1759, 32 George II. c. 14, it was increased to £5 per annum, for every person trading in silver wares of thirty ounces and upwards; wares in one piece not exceeding five pennyweights in weight being exempted.
The next change that took place was in the year 1784, 24 George III. c. 53, when a duty was again imposed of 6d.per ounce on silver plate. It was also enacted that the assay masters should stamp the work with the additional mark of the “King’s head,” as well as the others already ordered by the various Acts of the Legislature. The mark of the King’s head represented that of the reigning sovereign, and showed that the duty had been paid on the work. The present mark, therefore, is the Queen’s head.
By an Act passed in the year 1797, 37 GeorgeIII. c. 90, the duty on silver ware was increased to one shilling per ounce, but the Act which subjected silver wares to a duty of 6d.per ounce (24 George III. c. 53) has not been repealed, and is therefore in existence to this very day; by its provisions, however, the duty has been increased from time to time, until it has reached the amount at which it now stands.
The present annual licences of £2 6s.and £5 15s.respectively, were enacted in the year 1803 by an Act of 43 George III. c. 69, and by these regulations every person making or trading in silver wares, or otherwise dealing in the raw material, is compelled to take out an annual licence, or render himself liable to a penalty of £50.
Another Act was passed in reference to the duty on silver goods in the year following, 1804, 44 George III. c. 98, whereby it was increased to 1s.3d.per ounce. And in the year 1815, 55 George III. c. 185, the Act was further extended to 1s.6d.per oz. calculated in the manner we have described at the beginning of this chapter. To sum up, therefore, the silverdutiesin their several forms, bearing upon the trade at the present time, we find them as follows:—
Manufacturers of silver wares under 5 dwts. in weights.—Exempted from all duties.Vendors and dealers in silver wares under 5 dwts. in weight.—Exempted from all duties.Manufacturers of silver wares under 30 oz. in weight.—A plate licence of £2 6s. annually.Vendors and dealers in silver wares under 30 oz. in weight.—A plate licence of £2 6s. annually.Manufacturers of silver wares of more than 30 oz. in weight.—A plate licence of £5 15s. annually.Vendors and dealers in silver wares of more than 30 oz. in weight.—A plate licence of £5 15s. annually.Bullion dealers, refiners, and assayers.—A plate licence of £5 15s. annually.Manufacturers of plate.—A duty of 1s. 6d. per ounce.Hall-marked goods.—A duty of 1s. 6d. per ounce.
Manufacturers of silver wares under 5 dwts. in weights.—Exempted from all duties.
Vendors and dealers in silver wares under 5 dwts. in weight.—Exempted from all duties.
Manufacturers of silver wares under 30 oz. in weight.—A plate licence of £2 6s. annually.
Vendors and dealers in silver wares under 30 oz. in weight.—A plate licence of £2 6s. annually.
Manufacturers of silver wares of more than 30 oz. in weight.—A plate licence of £5 15s. annually.
Vendors and dealers in silver wares of more than 30 oz. in weight.—A plate licence of £5 15s. annually.
Bullion dealers, refiners, and assayers.—A plate licence of £5 15s. annually.
Manufacturers of plate.—A duty of 1s. 6d. per ounce.
Hall-marked goods.—A duty of 1s. 6d. per ounce.
Manufactured plate includes silver wares, such as spoons, forks, snuff-boxes, tea-sets, &c., and other articles used by the rich, and upon which the duty is compulsory; the duty on hall-marked goods, refers to all articles—with the exception of watch-cases, which are free—marked at the request of intended purchasers, which then pay duty on the manufacture of them. It will be observed from these remarks, that the silver trade generally is not at all affected by theduty tax; the wares manufactured by the trade at large not coming directly under the compulsory provisions of the law bearing upon this subject. It has been said that the silver trade ministers to luxury, and no doubt that portion of it which manufactures costly articles of plate for the wealthy does so; but we fail to see exactly, that the same remark appliesto that vast and increasing commercial industry which has sprung up of late years, and which bids fair to become one of the staple trades of the country. The duty-bearing articles are generally purchased by the classes of society who can well afford to pay the little extra which the duty imposes, and as the tax affects only that section of the silver trade which manufactures the article of luxury, it is not at all likely that the general trade would be increased by its entire removal. The duty, no doubt to most persons, may seem excessive, when calculated upon the percentage system; such for instance, as a tax of 20 per cent. upon spoons and forks; or one of 15 per cent. upon chains; or of 12½ per cent. upon tea-sets, &c.; this appears unjustly oppressive, and undoubtedly affects thesilver-platemanufacturer more vitally than any one else.
To the ordinary silversmith this question of duty is not likely to be of much importance; the agitation therefore commenced against it, may be expected to confine itself to those persons more directly affected, and whose interests would be advanced by its abolition.
The question of licences is one of far greater importance to the trade generally than that of duties, every manufacturer and dealer being compelledto procure a licence before he can carry on his business. If more direct action were taken in regard to this particular question, we believe that the whole trade would enter into it; for it resolves itself into this:—Why should the silversmith or goldsmith pay for a licence for the purpose of manufacturing and dealing, any more than the coppersmith, or the manufacturer of electro-plate, both of whom escape scot-free? We believe this to be an unjust tax, and that it ought not to be levied upon one particular trade any more than another. We have also distinctions made in the general class of silversmiths: we have those who may trade without any licence at all; those who may trade with a 46s.licence; and those who may trade with 115s.licence, that is, those who work or sell under 5 dwts., those who work or sell under 30 oz., and those who work or sell at any weight. Now this way of arranging the matter is very unsatisfactory to the trade generally; and any one of the first two traders to whom we have referred, is liable at any moment to be summoned before a criminal court for an infringement of the law, if he should happen to sell an article slightly over the weight for which he is duly licensed. At the present time a raid is being made upon the goldsmiths with referenceto this particular question, and a number have already been summoned for infringing their licences in this manner. However, there appears to be some doubt with respect to the Act of Parliament bearing upon the subject, as in most of the cases the defendants have gained a verdict, the line of defence on their behalf being, that the clause of the act which bore upon the cases referred to, meant the weight in fine metal,i.e.“pure gold,” of which the article was composed, and not that of the gross weight of the article sold. It was urged by those engaged in the various cases on the side of the defendants, that, for a 46s.licence, the vendor could sell an article in which the gold did not exceed two ounces, without any regard to the quality and weight made by alloy, and on this plea the magistrates granted them a verdict. In the higher courts we believe such verdicts would be reversed, for we firmly believe that the framers of the act meant no such thing, however defective may have been the legality of the points raised. The clause of the act to which we have alluded is No. 5, and runs as follows:—"All articles sold, or offered for sale, or taken in pawn, or delivered out of pawn, and alleged to be composed wholly, or in part, of gold or silver, are for the purposes of the above act to be deemed to be composedof gold or silver respectively; and if upon the hearing of any information for any offence against this act, any question shall arise touching thequantityof gold or silver containedin any article, theproof of such quantityshall be upon the defendant." The Excise authorities argue that this clause means that the absolute or gross weight of an article sold as gold must not exceed two ounces, and one sold as silver must not exceed thirty ounces, gross weight. If this view of the meaning of the act be eventually taken, and we believe it will, it will certainly operate to a greater extent against makers and vendors of gold articles than it will against silversmiths.
That part of theclausereferring to the quantity of gold or silver contained in a given article, we believe has reference to articles containing jewels, &c., in their construction, which renders it exceedingly difficult to get at their exact weight, when the work is finally completed with these jewels properly affixed upon it, and not to the amount of fine material any article may contain by assay. The last part of the clause we have marked in italics, “proof of such quantity shall be upon the defendant,” fully bears out these observations, because he is supposed to know the gross weight of any special article before the addition to it of any jewels.
We have been led to make these few remarks, in order to point out the gross anomalies which exist in the trade with respect to these licences, and to show the necessity of a reform taking place in a trade singled out from all the others, and made to pay a tax for the privilege of being allowed to make, or sell, articles in which gold or silver forms a component part. Therefore, if any action is to be taken in the matter, it must not be confined (if it is to be successful) to one particular branch of this important trade, but all must unite, and every influence should be brought to bear upon it in as forcible a manner as possible. The electro-plate manufacturer, and the dealer inhiswares, ought in all common fairness to the trade, to be put upon the same footing as the silversmith, if this licence is to be still continued. In electro-plating establishments, thousands of ounces of silver are being annually used on the surface of such wares as are manufactured there; and if such decisions as those lately given at the Thames and other police courts, with reference to the Act of Parliament on the subject of gold and silver wares are upheld, we fail to see how the manufacturers of silver-plated articles, who are continually making and selling them, containing as they do, more silver than the general public wouldsuppose, are to escape much longer these new interpretations of the Act of Parliament, and avoid being called upon to take out a licence in the same manner as the silversmiths. This is a tax in which the holder gets no direct return, and is levied in an unfair manner by the establishment of various grades of silversmiths, so that it gives a just cause for grievance. If the tax is to be upheld at all, why not make it equal by the establishment of one uniform rate for all trades alike?
CHAPTER XIV.
Useful Information for the Trade.
Silversmith’s Alloy.
Copper, 1 oz.; nickel, 3 dwts. 12 grs; bismuth, 6 grs.; zinc, 2 dwts. 12 grs.; soft iron, 12 grs.; tin, 12 grs. This compound is said to form a fusible and malleable metal, that can be easily worked by the silversmith; it is also said to resist oxidation through atmospheric influences.
Silver Wares.
Never scratch-brush silver ware with a solution of soap and water; neither should it be washed with the solution if it can be avoided, as it gives it the colour of pewter; better to scratch in weak ale, or if plain, rub it with a piece of wash-leather and prepared chalk.
Cleaning Plate.
Carbonate of ammonia, 1 oz.; water, 4 oz.; Paris white, 16 oz.; well mix the ingredients together, and apply to the surface of the plate by means of a piece of soft leather or sponge.
Imitation Silver.
Fine silver, 6 dwts.; nickel, 6 dwts.; copper, 8 dwts. This alloy will cost about 1s.9d.per ounce.
Another Recipe.
Fine silver, 5 dwts.; nickel, 6 dwts.; copper, 9 dwts. Cost about 1s.6d.per ounce.
Removing Gold from Silver Articles.
Silver articles which have been gilt, may be brought back to their original colour, by simply covering them with a thick solution of borax, and then well annealing them. After this process if the articles are boiled for a short time in one of the whitening mixtures and scratched, they will present a beautiful white and uniform surface.
Oxidizing Silver.
A beautiful deep black colour, possessing great lustre, may be given to finished silver work by boiling it in the following preparation for some time:—Bromine, 5 grs.; bromide of potassium, 5 dwts.; water, 10 oz. The boiling should beeffected in a stoneware pipkin, and generally from two to five minutes will suffice for the purpose. The work is finished after the proper colour has been attained, by well rubbing with a soft piece of wash-leather and a little best jeweller’s rouge. It is better to make the work as bright as possible before submitting it to this mixture; for this reason it is preferable to thoroughly buff all plain surfaces on a piece of felt by the application of the lathe, as by that means a characteristic brightness is imparted.
Dipping Mixture.
Brass or metal goods may be cleaned and their oxides removed by dipping into the undermentioned liquid for a few seconds only:—Oil of vitriol, five parts; water, five parts; nitric acid, two and a half parts; spirits of salts, two drachms. Well mix the several ingredients together, and immerse the work in the solution cold. The mixture improves after a quantity of work has been dipped into it.
Silver Powder for Copper.
Chloride of silver, two parts; cream-of-tartar, two parts; alum, one part. Mix with water to the consistence of a paste, and apply with a soft leather or sponge; when sufficiently whitened, well polish.
Powder for Silver.
Chloride of silver, 1 oz.; sal ammoniac, 2 oz.; sandiver, 2 oz.; white vitriol, 2 oz.; bichloride of mercury, 5 dwts. Make into a paste with water and rub the articles over with it; then expose them to a good heat upon a clear fire, in order to run the silver and evaporate the mercury, after which process dip in very weak sulphuric acid to clean.
To Protect the Polish of Metals.
Melt one part by weight of best wax paraffin and when sufficiently cooled, add three parts of petroleum. Well mix together, and apply to the polished articles by means of a soft brush. The protecting film is required to be only very thin, therefore too much should not be put on.
Silver Stripping Mixture.
Sulphuric acid, six parts; nitric acid, one part. Take a large black-lead crucible or pipkin, and heat the mixture in it; when this is done, put in the work required to be stripped, occasionally withdrawing it to ascertain the progress made. The large proportion of sulphuric acid allows of the dissolution of the silver, and does not sensibly corrode or interfere with copper, or any of its alloys, if kept quite free from water; therefore becareful not to introduce wet articles into the mixture. After finally withdrawing the work, it should be well rinsed, annealed, and then boiled out.
Stripping Silver.
Put some strong oil of vitriol in a similar vessel to those above described, apply heat, and during the process add a few crystals of saltpetre. When the solution has become hot enough the work should be immersed in it, and be moved about or agitated until the silver is dissolved from the surface. The articles should not be allowed to remain too long in the solution, and if it does not remove the silver quickly, more saltpetre should be added from time to time until the desired end be attained.
Soft Solder.
Pure tin, two parts; lead, one part. Melt and well incorporate together; when this is done pour into strips for use.
Soldering Fluid.
Muriatic acid (spirits of salts), three parts; metallic zinc, one part; or as much as the acid will take up. When dissolved and all effervescence ceases, allow it to settle, then decant the clearsolution from the sediment at the bottom of the vessel in which it has been made, and it is ready for use. If a small quantity of water be added to the mixture at this stage, say one-sixth, it will answer quite as well for some purposes. For soldering iron and steel, a very small portion of sal ammoniac is of great advantage to the mixture for promoting toughness.