The specimens taken from the tombs at Thebes are also numerous. Their rich and varied colors are proofs of the chemical and inventive skill of the ancients. These specimens embrace not only rich gems and mosaic work, but also fine examples of the lachrymatory vase. Some of the vases are made from common materials, with very great skill and taste. The specimen of glass coin, with hieroglyphical characters, must not be omitted; as also a miniature effigy of the Egyptian idol "Isis"; a specimen of which proves that the Egyptians must have been acquainted with the art of _pressing_ hot glass into metallic moulds, an art which has been considered of modern invention. English glass-makers considered the patent pillar glass a modern invention until a Roman vase was found (it is now to be seen in the Polytechnic Institution in London), being a complete specimen of pillar moulding. Pillat states in his work that he had seen an ancient drinking vessel of a Medrecan form, on a foot of considerable substance, nearly entire, and procured from Rome, which had the appearance of having been blown in an open-and-shut mould, the rim being afterwards cut off and polished. This is high authority, and, with other evidences that might be cited, goes far to prove that the ancients used moulds for pressing, and also for blowing moulded articles, similar to those now in use. Pompeian window-glass, of which panes have been discovered as large as twenty by twenty-eight inches, has proved, on examination, to have been cast in a manner similar to that now followed in making plate-glass, except that it was not rolled flat, as now, by metal cylinders, but pressed out with a wooden mallet, so that its thickness is not uniform. A glass has been discovered at Pompeii, about the size of a crown piece, with a convexity, which leads one to suppose it to be a magnifying lens. Now, it has been said that the ancients were not aware of this power, and the invention is given to Galileo by some, to a Dutchman, in 1621, by others, while a compound microscope is attributed to one Fontana, in the seventeenth century. But without a magnifying glass, how did the Greeks and Romans work those fine gems which the human eye is unable to read without the assistance of a glass? There is one in the Naples Royal Collection, for example, the legend of which it is impossible to make out, unless by applying a magnifying power. The glass in question, with a stone ready cut and polished for engraving, are now to be seen in the Museum of Naples.