only silver wire gilt, or covered with gold. An ingot of silver, usually about thirty pounds weight, is rounded into a cylinder, or roll, about an inch and a half in diameter, and twenty-two inches long. Two ounces of gold-leaf are sufficient to cover this cylinder: sometimes it is effected with little more than one. But this thin coat of gold must be yet vastly thinner. The ingot is repeatedly drawn through the holes of several irons, each smaller than the other, till it is finer than a hair: every new hole diminishes its thickness; but what it loses in circumference it gains in length, and consequently increases in surface: yet the gold still covers it: it follows the silver in all its extension, and never leaves the minutest part bare, not even to the microscope. How inconceivably must it be attenuated, when the ingot of silver is drawn into a thread, the size of which is nine thousand times less than it was at first.

CECILIA. This almost exceeds credibility. MR. HARCOURT. As inconceivable as it appears, the ingot is not yet extended to its full length. The greatest part of our gold

thread is spun, or wound on silk; and, before they spin it, they flatten it, by passing it through two rolls, or wheels of exceedingly well polished steel; which operation lengthens it one seventh, and, of course, diminishes its thickness, as well as increases the extension of the gold which covers it, to such an exquisite thinness, that M. Reaumur calculates that it is reduced to less than the three millioneth part of an inch!

SOPHIA. Imagination can scarcely follow such nice calculations. The fineness of the spider's web, with which we were amused some time ago, is the only thing that I know of, which bears any comparison with it. Glass, I think, possesses a capacity also of being drawn into threads. I remember to have been shown what they call spun-glass, when I was at the glass-house: it resembled a skein of fine silk, and formed a pretty ornament for a head-dress.

MRS. HARCOURT. Several other substances possess a degree of ductility, but very inferior to that of gold. Gums, glues, resins, and some other bodies, may, when softened by

water, be drawn into threads. Silver we have just proved to be ductile: the rest of the metals have this property, more or less. Gold only dissolves in aqua regia. When ether is mixed with the solution, it attracts the gold to itself; and was formerly exhibited in medicine, under the name of potable or drinkable gold. Gold undergoes the operation of fire without the smallest diminution. Platina and silver are the only metals besides, which do not lose their metallic appearance, and either evaporate in flame, or change into an earthy or glassy form.

CHARLES. This accounts for a comparison which I have frequently heard, of virtue resisting temptation, as gold tried in the fire.

MR. HARCOURT. This power of resisting the action of fire, peculiar to these metals, has given them the denomination of perfect and noble; in opposition to the rest, which are called imperfect, because they are reduced by being kept long in a fierce fire, to a calx, which, you may recollect, is used by the enameller. The calx is heavier than the metal itself, and is composed of the metal and a portion of the air united to it.

SOPHIA. Are not metals said to be alloyed, when they are mixed with an inferior kind?

MR. HARCOURT. Yes: gold and silver coins are never struck without an alloy of copper. The softness of these metals is the principal reason of their being mixed or alloyed, with design to render them harder. Were not gold so rare, it would be admirable for many domestic utensils, as its most valuable quality is, that it never rusts or tarnishes.

CECILIA. Nothing could be so beautiful as gold for such purposes. Its brightness, its colour, and cleanliness, to say nothing of its magnificence, would give it a superiority to every other metal. Is this precious substance peculiar to any part of the globe?

MRS. HARCOURT. The knowledge that Charles has acquired, of the productions of different countries, will enable him to reply to this question.

CHARLES. It is found in all the known parts of the earth, though very unequally with respect to purity and abundance. The most considerable mines in Europe, are those of the Upper Hungary, and particularly that

of Chremnitz. America yields the greatest profusion of gold, of any of the four quarters of the world. Peru, Mexico, Chili, and other provinces of the Spanish West Indies, to which I may add the Brazils, abound with it. When the Spaniards first visited these countries, they found a temple, the walls of which were covered with gold.

HENRY. I wish it were so plentiful in England, we might then use it as commonly as the ordinary metals.

SOPHIA. Let us be contented with the use of iron, and the other inferior metals, which are well adapted to most of our domestic wants, without coveting the, riches of the Peruvians to these harmless people they were a source of the greatest misfortunes.

AUGUSTA. How so? I thought wealth had always been a sign of national prosperity.

SOPHIA. You have already forgotten what papa remarked upon that subject last night, or you would have been of a different opinion. The richness of the Peruvian mines attracted the covetousness of the Spaniards, by whose rapacity their government was subverted, and the whole nation finally destroyed.

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