Rubies are even now scarce in India, and probably always will be, since the demand for them is very great among the wealthy of the populous nations of that country. Even three centuries ago Tavernier found it profitable to buy them in Europe and sell them again in the country whence they had been taken perhaps many centuries before. Red sapphires not only exhibit singular internal structures, but they may be colored strangely, thus puzzling the experimentalist to account for the distribution of coloring matter. Davila possessed a fine and rare ruby which exhibited a clear white band between two parts of red. Another gem showing a strange arrangement of color was to be seen in the cabinet of Chantilly. It was half red and half yellow. Stones of such distribution of color are marvels of rarity; but it is quite common to meet with them partly red and blue or white, or blue and yellow. They sometimes display a vague dichroism which is not so well defined as in the iolite or tourmaline. The naturalist Fanjas found at Expailly, in France, a transparent sapphire which, viewed in one direction, exhibited a green hue approaching the emerald in its beauty of tint, but when seen in another light it appeared of a very beautiful blue. In the Orleans collection there was a curious sapphire which had been engraved with the figure of a woman, the head being formed of white, and the dress of intense blue. It is related that M. Bossi, of Milan, who was an excellent connoisseur in gems, saw in possession of Prince Metsch a superb sapphire which appeared to be dotted with flakes of gold. We sometimes notice this singular appearance in the interior of other gems, and find by the use of the microscope that it is due to internal flaws or reflections from plate-like crystals within the stone. We are inclined to believe that this gem of Prince Metsch is to be classed with the sapphire owned by Abbé Pullini, which had been engraved upon by the ancients. This stone, when viewed in a certain direction, exhibited flakes of gold in the interior, which disappeared when the view was changed, which would hardly have been the case if the reflections had been produced by opaque bodies. We have before us a polished Siberian beryl which shows flakes of silver-white in certain lights, but which appear of dark-brown when the axis of vision is changed.