568 EMERALD EMERSON Aztecs, one in the form of a rose, the second in the form of a horn, the third like a fish with eyes of gold, and the fourth like a little bell, with a fine pearl for the tongue ; the fifth, which was the most valuable, was a small cup with a foot of gold, and with four little chains of the same metal attached to a large pearl as a button. From these sources were probably obtained the magnificent emeralds now in the royal collection at Madrid, some of which are stated to be as large as those of the duke of Devonshire, and of the finest water. The em- erald has long been highly esteemed, ranking in value next to the diamond and the ruby. Pliny states that in his time those of considerable size, which were free from defects, were sold at enormous prices. The color of the emerald is of a finer green than that of any other stone, having different shades, some of verdigris or grass green, and some of a paler hue. They all appear best by daylight, and to retain their effect by candle light they require to be set with small diamonds or pearls. Emeralds are generally cut in the form of a square table, with bevelled edges, the lower surface being cut into facets, parallel to their sides. Beudant, in his Mineralogie, gives the value of emeralds of fine colors, and free from flaws, as follows : one of 4 grains, 100 to 120 francs; of 8 grains, 240 francs; of 15 grains, as high as 1,500 francs ; and he cites a fine stone of 24 grains which was sold at 2,400 francs. Immense emeralds are men- tioned by ancient authors, but they were un- doubtedly glass imitations. Such was the colossal statue of Serapis in the Egyptian laby- rinth, 13 ft. high; also an obelisk in the temple of Jupiter, 60 ft. high and 6 ft. broad, composed of four pieces. Sir J. Gardner Wil- kinson remarks that the forming of these huge blocks of glass was a greater triumph of art than imitating the stones. Egypt was the country especially noted for the manufacture of artificial emeralds, and Pliny says that they succeeded so completely that it was " difficult to distinguish false from real stones." The oriental is not, like the true emerald, a silicate of alumina and glucina, but is a green, trans- parent variety of corundum, and therefore near- ly pure alumina, differing from the sapphire only in color. It is the rarest of gems, and from this and its superior hardness, although inferior in color, it is highly prized. Mr. Eman- uel of London says that he has only met with one specimen; but in the autumn of 1872 Dr. J. Lawrence Smith had sent to him from the territory of Montana a quantity of rolled peb- bles, which were found to be corundum. They were flattened hexagonal prisms with' worn edges, and were either colorless or green, vary- ing in shade from light to dark; none were red. They are found on the Missouri river, near its source, about 160 m. above Benton, and are obtained from bars on the river, where considerable gold is also found. The corundum is scattered through the gravel, which is about 5 ft. in depth, lying upon the bed rock. It is most abundant on the Eldorado bar, 16 m. from Helena. One man could collect on this bar from one to two pounds per day. Dr. Smith has had some of the stones cut, one of them very perfect, of 3 carats, of a fine green, almost equal to the best oriental emerald. EMERALD HILL, a municipal town of Vic- toria, Australia, 1 m. S. of Melbourne; pop. in 1871, 17,121. It has a mechanics' institute with a library of 2,350 volumes, several public buildings, and a weekly newspaper. It was one of the earliest municipalities of the colony, being proclaimed in May, 1855. EMERSON, George Barrel), an American edu- cator, born in Kennebunk, York co., Maine, Sept. 12, 1797. He graduated at Harvard college in 1817, and soon after took charge of an academy in Lancaster, Mass. Between 1819 and 1821 he was the tutor in mathematics and natural philosophy in Harvard college, and in 1821 was chosen principal of the English high school for boys in Boston. In 1823 he opened a private school for girls in the same city, which he conducted till 1855, when he retired from professional life. He wrote the second part of the "School and Schoolmaster," of which the first part was written by Bishop Potter of Pennsylvania, and is the author of a number of lectures on education. He was for many years president of the Boston society of natural history, and was appointed by Gov. Everett chairman of the commissioners for the zoologi- cal and botanical survey of Massachusetts. He has published a "Report on the Trees and Shrubs growing naturally in the Forests of Massachusetts" (Boston, 1846), and a "Manual of Agriculture " (1861). EMERSON, Ralph Waldo, an American poet and essayist, born in Boston, Mass., May- 25, 1803. He is the son of the Rev. "William Em- erson, pastor of the first church in that city. In his eighth year, on the death of his father, he was sent to one of the public grammar schools, and was soon qualified to enter the Latin school. Here his first attempts in liter- ary composition were made, consisting of ori- ginal poems recited at exhibitions of the school. He entered Harvard college in 1817, and grad- uated in August, 1821. He does not appear to have held a high rank in his class, though the records show that he twice received a Bowdoin prize for dissertations, and once a Boylston prize for declamation. He was also the poet of his class on " class day." While at the uni- versity he made more use of the library than is common among students, and was distinguished among his classmates for his knowledge of gen- eral literature. For five years after leaving college he was engaged in teaching school. In 1826 he was "approbated to preach" by the Middlesex association of ministers; but his health at this time failing, he spent the winter in South Carolina and Florida. In March, 1829, he was ordained as colleague of Henry Ware, at the second Unitarian church of Bos- ton. He belongs to a clerical race. For eight
