shut the cock C to cut off the communication between 1816. G, the glass globe receiver, and T, the glass tall receiver, and also shut the cock O.

of

The apparatus being now ready to receive the sun's rays through the powerful lens L, converge these rays to a point to impinge upon the diamond D. In a short time a most brilliant combustion takes place, in consequence, perhaps, of being burnt in oxygen gas. The diamond is entirely consumed, and disappears, being converted into carbonic acid gas. The weight of the globe receiver, together with the weight of the volume gas therein, is to be noted down before the diamond was placed in the platina capsule, in doing of which the oxygen gas is of course drawn out or has escaped, but when the diamond has been properly placed, the globe is refilled with the oxygen gas, preparatory for combustion. Agreeing, then, that the oxygen gas in refilling the globe the second time is exactly the same weight as the first time, the difference, after the combustion of the diamond, should, on weighing the globe, be exactly an increase of weight of ten grains, which will be found to be the case if the experiment is scientically and nicely performed.

There are few things in the history of mankind that, at first sight, appear so remarkable as the prodigious value which, by common consent, in all ages, and in all civilized countries, has been attached to the diamond. It would almost seem incredible that a transparent crystallized stone, about the size of a pullet's egg, should have been sold for £90,000 in money, an annuity of £4,000 besides, and a patent of nobility into the bargain; but all this was given, by the Empress Catherine of Russia, for the famous diamond of Nadir Shah!

1816.

Among ornaments and luxuries, Diamonds unquestionably occupy, and have ever occupied, the highest rank. The beauty of this gem depending on its unrivalled lustre is, no doubt, the circumstance which originally brought it into notice, and certainly, notwithstanding the smallness of its bulk, there is no substance, natural or artificial, that can sustain any comparison with it in this respect. The varied and vivid refractions of the Opal -the refreshing tint of the Emerald the high coloured lustre that distinguishes the Ruby-the ethereal light that streams from the Sapphire-and the golden rays that emanate from the Topaz-beautiful as they are, seem lost, at a small distance, in comparison with the Diamond, which, although it has no colour of its own, imbibes the pure solar ray, reflects it with undiminished intensity, and refracts it into such prismatic colours, combining unequalled brilliancy; and whether blazing on the crown of state, or diffusing its starry radiance from the breast of titled merit, in courts or high solemnities, it proclaims to the most distant circle of the surrounding crowd the person of the monarch, of the noblesse, or of the beauty.

Diamonds of a large size are so rare, that their number scarcely amounts to twenty-five in the world, and, perhaps, only about two-thirds of that number in Europe. These are nearly in the possession of sovereign Princes; hence the acquisition of a moderate size diamond is what mere money cannot always command.

When the Czar Peter the Great, and his whole army, was surrounded by the Turks, he owed his safety to the fascinating splendour of the diamonds of his Empress !

The regent diamond of France was played by the Abbé Sieyes with such success before the Sovereign of

Prussia as to produce for the service of France 40,000 1816. horses, with their equipments.

The only places where this extraordinary gem has been found, in modern times, are the southern parts of India Proper, the peninsula of Malacca, the island of Borneo, and the mountainous district called Serro do Frio, in the Brazils. Neither the rock in which it occurs, nor the other minerals with which it is accompanied, in Malacca, and in the island of Borneo, are at all known ; but in the southern part of India the class of minerals which accompany diamonds is better understood.

There are four diamond mines in the East, three of which are situate within a few days' journey of Golconda. One of these is called Ralconda, which produces in general very small stones, seldom more than three carats in weight. The mine called Coulour is famous for diamonds of a large size-from ten to forty carats; now a carat of diamond is equal to four grains, which must not be confounded with a carat of gold, as a carat of gold is twelve grains.

It was in the mine of Coulour that the wonderful diamond of Aurez Seb, the Great Mogul, was found, and which weighed 795 carats. The stones in this mine are not very clear, and, extraordinary to tell, are generally tinged with the colour of the soil. There are generally many thousands of men, women, and children, at work in this mine.

The third mine is that of Samalpour, which lays nearer to Bengal. This mine is actually in the bed of the river, and is the mine which produces the natural sparks, or diamond points, used by glaziers for the purpose of dividing plates of glass.

The mine in the island of Borneo is in the bed of the

I