CLINTON, a city and the county-seat of Henry county, Missouri, U.S.A., on the Grand river, 87 m. S.E. of Kansas City. Pop. (1890) 4737; (1900) 5061 (470 being negroes); (1910) 4992. It is served by the St Louis & San Francisco, the Missouri, Kansas & Texas, and the Kansas City, Clinton & Springfield railways. The city is situated on the border of a rolling prairie about 770 ft. above the sea. The vicinity abounds in coal, but is principally agricultural, and Clinton’s chief interest is in trade with it. The principal manufactures are flour and pottery. Clinton was laid out in 1836 and was incorporated in 1865.
CLINTON, a village of Oneida county, New York, U.S.A., on the Oriskany Creek, about 9 m. S.W. of Utica. Pop. (1890) 1269; (1900) 1340; (1905) 1315; (1910) 1236. It is served by the New York, Ontario & Western railway, and is connected with Utica by an electric line. Several fine mineral springs in the vicinity have given Clinton some reputation as a health resort. There are iron mines, blast furnaces, and iron smelters. Clinton is the seat of Hamilton College (non-sectarian), which was opened as the Hamilton Oneida Academy in 1798, and was chartered under its present name in 1812. It was founded by the Rev. Samuel Kirkland (1741-1808), a missionary among the Oneida Indians; its corner-stone was laid by Baron Steuben; its shade trees were furnished by Thomas Jefferson; and its name was received from Alexander Hamilton, one of its early trustees. It had in 1907-1908 20 instructors, 178 students, and a library of 47,000 volumes and 30,000 pamphlets. At Clinton are also excellent minor schools. Litchfield Observatory is connected with the college, and was long in charge of the well-known astronomer, Christian H. F. Peters (1813-1890), who discovered here more than 40 asteroids and made extensive investigations concerning comets. The village was settled about 1786 by pioneers from New England, was named in honour of George Clinton, and was incorporated in 1842.
CLINTONITE, a group of micaceous minerals known as the “brittle micas.” Like the micas and chlorites, they are monoclinic in crystallization and have a perfect cleavage parallel to the flat surface of the plates or scales, but differ markedly from these in the brittleness of the laminae; they are also considerably harder, the hardness of chloritoid being as high as 6½ on Mohs’ scale. They differ chemically from the micas in containing less silica and no alkalis, and from the chlorites in containing much less water; in many respects they are intermediate between the micas and chlorites.
The following species are distinguished:—
Margarite is a basic calcium aluminium silicate, H2CaAl4Si2O12, and is classed by some authors as a lime-mica. It forms white pearly scales, and was at first known as pearl-mica and afterwards as margarite, from μαργαρίτης, a pearl. It is a characteristic associate of corundum, of which it is frequently an alteration product (facts which suggested the synonymous names corundellite and emerylite), and is found in the emery deposits of Asia Minor and the Grecian Archipelago, and with corundum at several localities in the United States.
Seybertite, Brandisite and Xanthophyllite are closely allied species consisting of basic magnesium, calcium and aluminium silicate, and have been regarded as isomorphous mixtures of a silicate (H2CaMg4Si3O12) and an aluminate (H2CaMgAl6O12). Seybertite (the original clintonite) occurs as reddish-brown to copper-red, brittle, foliated masses in metamorphic limestone at Amity, New York; brandisite as yellowish-green hexagonal prisms in metamorphic limestone in the Fassathal, Tirol; xanthophyllite as yellow folia and as distinct crystals (waluewite) in chloritic schists in the Urals.
Chloritoid has the formula H2(Fe,Mg)Al2SiO7. It forms tabular crystals and scales, with indistinct hexagonal outlines, which are often curved or bent and aggregated in rosettes. The colour is dark grey or green; a characteristic feature is the pleochroism, the pleochroic colours varying from yellowish-green to indigo-blue. Hardness, 6½; specific gravity, 3.4-3.6. It occurs as isolated scales scattered through schistose rocks and phyllites of dynamo-metamorphic origin. The ottrelites of the phyllites and ottrelite-schists of Ottrez and other localities in the Belgian Ardennes is a manganiferous variety of chloritoid, but owing to enclosed impurities the analyses differ widely from those of typical chloritoid.
(L. J. S.)