METHOD OF OBTAINING GOLD.

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Remark. ..One grain of gold may easily be divided into twomillions of parts; and a cubic inch of gold, into nine thousandfive hundred and twenty-three millions, eight hundred and ninethousand five hundred and twenty-three parts, each of whichmay be distinctly seen by the naked eye.

Boyle, quoted by Apligny in his Treatise of Colours, says, thatone grain and a half of gold may be beaten into 50 leaves of oneinch square, which if intersected by parallel lines drawn at rightangles to each other, and distant only the 100 th part of an inchfrom each other, will produce 25 millions of little squares, eachof which may be distinctly seen Avithout the help of glasses.

Mr. Magellan has informed us that its surface .may be ex-tended by the hammer 159,092 times, and that the finest gold-leaf is that made in new skins, which must have an alloy ofthree grains of copper to the ounce troy of pure gold, or it wouldbe too soft to pass over the irregularities of the skin.

He affirms, that SO books, or 2000 leaves of gold, each mea-suring 3.3 square inches, viz. each leaf containing 10.89 squareinches, weigh less than 3S4 grains. Each book therefore, or 25leaves = 272 .23 inches, weigh less than 4.S grains; so thateach grain of the metal will produce 56.718 square inches.From further calculations it may be made evident, that thethickness of these leaves, is less than ^ - a ^ th of an inch; andthat sixteen ounces of gold, which if in the form of a cube,would not measure more than one inch and one quarter on itsside, will completely gild a silver wire sufficient in length to goround the whole earth like a hoop.

METHOD OF OBTAINING GOLD.

The processes for obtaining gold, in the large way, from itsdifferent native combinations, or admixtures, vary, according tothe state of the gold, and the nature of the substances Avhich arefound mixed with it.

Vol. 11.

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