rich commercial nation, as London is, that it encourages many to excel in the different branches of the art, and supplies the artificers with employment; though they may be divided into many kinds, as the jeweller, the snuffbox and toy-maker, the silver-turner, the gilder, the burnisher, the chaser, the refiner, and the gold-beater. As we have treated of gold from the mine to the hand of the consumer, we will proceed to some particulars relative to silver, if you are not weary, children, of the subject.

SOPHIA. I can speak for myself, that I have been so well entertained, I shall be highly gratified by hearing the properties of all the rest of the metals.

All. We are all of one mind.

MR. HARCOURT. Silver is the most precious, the finest, the purest, and most ductile, of all the metals after gold, and possesses many of the same properties, though not in so great a degree: its ductility, or capacity of extension, has already been instanced, in the fineness to which the wire is drawn that is to be covered with gold. It is as fixed and inde

structible as gold, bearing the action of fire, without a diminution of its weight. It contracts no rust, but is very apt to tarnish, as you may have often observed, which effect arises from its attracting sulphur from the air. It is harder than gold; and if you take the silver mug, and ring it, you will perceive that it has a sonorous quality. Charles, I shall not infringe upon your office of pointing out the countries where silver-mines are the most productive.

[ocr errors]

CHARLES. Every quarter of the globe contains some veins of this metal. Nor is our own island destitute of it; for although we cannot boast of any silver-mines, properly so called, yet several of our lead-mines yield a considerable proportion of silver. It is said that Sir Hugh Middleton, the projector of bringing the New River from Ware to London, was enabled to prosecute his useful design, by which a great part of the inhabitants of the metropolis is supplied with water, from the silver produced by his lead-mines in Wales. The mines of Peru, and other parts of South America, are much the most abundant of any

known; particularly those of Potosi, which continue to repay the labour of the miners, notwithstanding the immense quantities that have been dug out of them. Instead of finding the ore near the surface, as they formerly did, the workmen are now obliged to descend to prodigious depths, in order to obtain it. So poisonous are the exhalations which issue from them, that many thousands of Indians have perished in them, and prodigious numbers are still sacrificed there, by avarice, every year. The cattle which graze on the outside are affected by the pernicious effluvium; but so great is its power over the miners withinside, that none of them can resist its influence above a day together. As a means of prevention, these poor people drink an infusion of an herb called paraquay.

CECILIA. Our rich sideboards of plate may then be said to be purchased at the price of the health and lives of our fellow-creatures.

MR. HARCOURT. Mining is, in many respects, a dangerous and disagreeable employment; but views of present advantage will induce the ignorant and inconsiderate to

undertake almost any task, however objectionable. Silver is found in different states. It is called virgin, or native silver, when it occurs naturally alloyed with copper and gold; but this is but rarely to be met with. When it does happen, it is usually in fibres, grains, or crystallizations, lying in different substances, as flint, spar, slate, &c. but it is generally found in a mineral state, by which I mean, united with matter foreign to itself. Silver is capable of being alloyed with all metals, and forms different compounds with them, according to the nature of the mixture. When dissolved in aqua fortis, and the moisture evaporated, it is called lunar caustic. If you dissolve this in water, and write a letter with the solution, the writing will be invisible till it is exposed to the rays of the sun, when it soon becomes nearly as black as common ink.

SOPHIA. Although the exhalations of silver mines are so poisonous, silver is thought the wholesomest of all metals; which is the reason that spoons are generally made of it, and saucepans, where people can afford it. Grand

mamma has one, which she lays aside for the use of any of the family who are indisposed.

MR. HARCOURT. Gilding and silvering are performed by processes very similar to one another, whether on metal, wood, leather, or paper. The method by amalgamation you have already heard. In many cases, the substance intended to be gilt, is daubed over with size, composed of different materials, and the gold or silver leaf laid upon it.

HENRY. Oh! that was the way my brother used to gild the carp in the fish-pond.

MRS. HARCOURT. How was that, Charles? you must tell us your secret.

CHARLES. I made a mixture of Burgundy pitch, powdered amber, and several other ingredients, and after rubbing my fish quite dry, I smeared him over with it, and then pressed on the gold leaf gently with my hand; upon which I dismissed my poor prisoner with his splendid habit, to his native element, better pleased with his release than with his new finery, which he did not understand.

MRS. HARCOURT. Late as it is, I cannot refuse you the pleasure of seeing a pretty

« VorigeDoorgaan »