Page:The American Cyclopædia (1879) Volume XI.djvu/650

632 MIRROR the princess. In the Bible she is called "the prophetess ;" and after the passage of the Red sea she headed the triumphal procession of women, and led their song of victory. Having together with Aaron spoken against Moses in the desert, on account of his having married an Ethiopian (Cushite) woman, she was struck with leprosy, and was excluded from the camp seven days. According to Josephus, she was the wife of Hur, and grandmother of Bezaleel, the architect of the tabernacle. Her- name is the Hebrew form of Mary, and the Arabic traditions confound her with the Virgin Mary. She died in Kadesh. MIRROR (Fr. miroir, from Lat. mirari, to wonder, admire), a looking glass or speculum ; any bright surface that reflects the rays of light falling upon it. The surface of smooth water is a natural mirror, which the ancient poets sometimes refer to as having been used by persons for viewing their own forms. Me- tallic mirrors are mentioned in Exod. xxxviii. 8, and Job xxxvii. 18. With the ancient Egyptians one of the principal articles of the toilet was the mirror. Wilkinson says it was of mixed metal, chiefly copper, carefully wrought and highly polished. It was circular, and had an elaborately ornamented handle, the designs of which were sometimes beautiful female figures, and sometimes hideous monsters, whose ugliness contrasted most strongly with the features reflected by its polished surface. The practice of using polished basins for mir- rors is alluded to by Artemidorus; and the ancients also had drinking vessels, as men- tioned by Pliny, the inside of which was so 'cut and polished that the image of one drink- ing from them was reflected many times. The composition of some of the ancient mirrors has been found by William Francis to have been: copper 67'12, tin 24*75, and lead 8'13 parts in 100; and by Klaproth: copper 62, tin 32, and lead 6 per cent. Their manufac- ture appears to have been most extensively carried on at Brundusium. Pliny gives to Pasiteles, a native of S. Italy and contempo- rary of Pompey, the credit of introducing mir- rors of silver. They are spoken of by Plautus, and in the time of the first emperors they be- came very common among the Romans, so that they were in use, according to Pliny and Sene- ca, even by maid servants, and the manufacture of them was one of the important trades of Rome. From several statements of Pliny it appears that various stones were employed as mirrors, set into the walls as panels, and other- wise used to reflect images of objects. Ob- sidian appears to have been most employed for this purpose. A similar stone called the itztli, and by the Spaniards gallinazo, was used for the same purpose by the Aztecs, of which hard vitreous stone they also fashioned sword blades and razors. There were other stones of which they made excellent mirrors; but the description of these is too indefinite to de- termine their names. Beckmarm thinks that the use of the dark obsidian stone for mirrors suggested the use of glass, that this was at- tempted at the celebrated glass works of Sidon of which Pliny makes mention, and that they were first made of black glass, and afterward of glass covered on the back with black foil. But from the time of Pliny no certain refer- ence is again found to glass mirrors until the 13th century. In the treatise on optics of Alhazen, the Arabian, of about the year 1000, mention is made of mirrors of iron (steel) and also of silver, but not of glass ; and the same thing is remarked of the " Optics " of Vitello, of about the middle of the 13th century. But in the treatise on optics of John Peckham, an English Franciscan monk, who taught at Oxford, Paris, and Rome, and died in 1292, mirrors of iron, steel, and polished marble are spoken of, and also of glass covered on the back with lead. After this time various writers allude to mirrors of this sort, and describe their being made by pouring melted lead over the hot glass plates. In the 14th century glass mirrors were extremely rare in France, while metallic ones were in common use. Beck- mann describes the following method of pre- paring small convex glass mirrors as common in Germany in the beginning of the 16th cen- tury: A hollow ball of glass being blown, while it was still hot a metallic mixture of lead or tin and antimony, with a little resin or salt of tartar, was introduced into it, and coated its inner surface, the resin or salt aid- ing the fusion of the metal and preventing its oxidation. The glass, being entirely coated within, and having become cool, was cut into small round mirrors. It is not many years since they were sold in Germany by the name of Ochsenaugen, ox eyes. They were set in a round painted board, and had a very broad border, and reflected a diminished but very clear image. The coating of glass with an amalgam of tin foil and mercury was practised by the Venetians in the 16th century. The process, as described by Porta, who witnessed it at Murano, consisted in spreading the tin foil smoothly upon a plane surface, and pour- ing upon it mercury, which was rubbed in with the hand or a hare's foot. The amalgam thus formed was then covered with a sheet of paper, and the glass being laid upon this and pressed down, the paper was drawn out. Weights were then laid upon the glass, and it was left for some time for the excess of mer- cury to drain off. The introduction of this manufacture into France is noticed in the article GLASS. The chief modern improve- ment in the art consists in the use of very large plates, the process of coating them not differing essentially from that of the Vene- tians 300 years ago. The present method is as follows: A large stone table, ground per- fectly smooth, is so arranged as to be easily canted a little on one side by means of a screw set beneath it. Around the edges of the table is a groove, in which mercury may