Page:Popular Science Monthly Volume 47.djvu/437

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Philadelphia, and fifteen miles north of the Maryland border. It lies in the midst of mica schists, presumably Archæan, in what was called the middle gneissic belt by H. D. Rogers, and the Georgetown series by Persifor Frazer. This formation is quite narrow in the vicinity of the mine, and pinches out to the westward, from the coming in of the limestone on the north and south sides. The dark, basic rock with which the ore is associated forms a lenticular mass of rock, which consists most largely of green secondary hornblende, and often shows almost nothing else than this mineral. It is called hornblende at the mine, and is best described by the word amphibolite as a rock name. The pyrrhotite lens on Anthony's Nose, near Peekskill, on the Hudson, is quite different in its geological relations from the Gap mine. It is situated on the northern side of the mountain, about seven hundred feet above tide water, and three miles from Highlands Station. The general geology consists of the usual gneisses of these old formations. Several well-known iron mines lie about twenty miles northeast. The ore bed was opened shortly after the war, when it was known as the Phillips Mine, and was operated for ten or fifteen years, but for sulphur fumes, and not for its metallic contents, which proved too low for profit. Other minor nickel-bearing beds have been noticed along the Hudson. Openings for nickel in gneiss have also been made at Litchfield, Conn.; at Dracut, near Lowell, Mass.; and perhaps at other points. The geological relations seem to be practically the same as those along the Hudson. These ores and the formations in which they occur have been fully described in a paper of the Geological Department of Columbia College, by J. F. Kemp, in the light of Prof. Vogt's views of the igneous origin of the ores.

The Former Antillean Continent.—The theory of a former kind of continental extension—the Antillean continent—which united the West Indies to the mainland, excluding the Atlantic waters and admitting the Pacific waters into the Mexican Gulf and the Caribbean Sea, has been examined in the light of the geographical and geological evidences by J. W. Spencer, who has attempted to restore the topography of the submerged continent and to set forth the geomorphic evidence that the drowned valleys of the Atlantic coasts are the valleys of former lands now depressed beneath the sea. These valleys or fiords are very numerous, and many of them are traceable to depths of more than two miles along the Atlantic, Gulf, and Caribbean coasts. The measurements of them give data for calculating the late elevation of the region. From the application of the continental movements it becomes apparent that the mainland stood as high as the fiords are deep, less some correction for unequal subsidence of the continental region. Accordingly, it is concluded that the Antillean bridge stood at from one and a half to two and a half miles above the present altitudes of the plains that now form the islands, with their mountains relatively somewhat lower than at present. The formations out of which the valleys are excavated belong mostly to the more recent geological periods, and are generally but little disturbed. From the determination of their age and that of the materials filling the buried valleys, it has been found that there were two epochs of great elevation, namely, in the Pleiocence and in the Pleistocene periods. Between these there was a subsidence of such depth as to drown the continental coastal plains, and reduce the West Indian region to very small islands, with (probably) a shallow connection between the Atlantic and Pacific coasts.

The Gothenburg System.—What is called the Gothenburg system of regulating the sale of intoxicating liquors is undergoing fierce criticism in England, where its adoption is favored by the Public-House Reform Association, founded by the Bishop of Chester. Under this system the traffic is made a concern of the community, and is carried on in its behalf by a company to which it is committed under conditions. The principles of the theory of popular control of the liquor traffic are summarized by the Rev. F. S. McC. Bennett, Honorary Secretary of the Public-House Reform Association, as being that licenses, though they have been granted for years to private persons and have been renewed with such regularity as to give them a marketable value, are essentially local public property, and the community, while bound to recognize the equitable claims of those whom it