year had made himself acquainted with 13 languages, among which were Arabic, Persian, Hindustani, Sanskrit, and Syriac. When 10 years old he began the study of mathematics, and at 17 presented a paper to Brinkley, the Irish astronomer-royal, which exhibited such a profound knowledge of mathematics, that the latter declared the author of it to be already the first mathematician of his age. In 1827, the chair of astronomy in Trinity College, as well as the post of astronomer-royal, becoming vacant, Hamilton obtained both appointments, though then only in his 23d year. His life henceforth was exclusively devoted to abstruse studies. He was knighted in 1835; in 1837 was elected president of the Royal Irish Academy, and was an honorary or corresponding member of the principal scientific academies of Europe and America. In 1828 his Theory of Systems of Rays' was published. In this his celebrated prediction, on theoretical grounds, of the existence of conical refraction of a ray of light was given to the world. Reasoning on the properties of light, he came to the conclusion that under certain circumstances a ray, instead of being refracted in the ordinary way, should split up into a cone of rays; a phenomenon afterward proved experimentally by Lloyd to take place under proper conditions. In 1834 his General Method in Dynamics' was published. In this work and that on Systems of Rays the whole of any dynamical problem is made to depend on a single function and its differential coefficients. Another important treatise of his is Algebra looked on as the Science of Pure Time.' He published_also 'Memoirs on Discontinuous Functions, or Equations of the Fifth Degree, etc.) But the foundation on which his fame most securely rests is the discovery or invention of the calculus of quaternions, an instrument of extraordinary power in the solution of intricate problems in mathematics and physics. His Lectures on Quaternions appeared in 1853, and in 1866 a posthumous work on the same subject entitled Elements of Quaternions.' See Life of Sir William Rowan Hamilton,' by Graves (1883-9), with an Addendum (1892).

Hamilton, Bermuda, a seaport town, the capital of the Islands on Great Bermuda, Long, or Hamilton Island. It has a fine landlocked harbor. Founded in 1790. Pop. (1901) 2,246.

Hamilton, N. Y., a village of Madison County, 29 miles southwest of Utica, on the New York, O. & W. R.R. It is the seat of Colgate University (q.v.). It is in a good agricultural region, contains a lumber yard and canning factory, and has a stone quarry, from which the stone for the construction of most of the University has been taken. Hamilton was first settled in 1792, was separated from the township of Paris in 1795, and named in honor of Alexander Hamilton; the village was incorporated 12 April 1816; in 1895 a fire destroyed the business portion of the town, in which the village records were lost. Later in the same year, waterworks and an electric lighting plant were established, which are owned and operated by the town. In 1903 a free library was opened by the Library Association, and it is intended to make it a public library supported by the village corporation. (Pop. 1900) 1,627.

Hamilton, Ohio, city, county-seat of Butler County: on the Great Miami River, the MiVol. 7-55

ami & Erie Canal, the Pittsburg, C., C. & St. L., and the Cincinnati, H. & D. R.R.'s; about 15 miles north of Cincinnati, and 32 miles southwest of Dayton. Gen. Arthur Saint Clair established here a fort, in 1791, and called it Fort Hamilton, in honor of Alexander Hamilton. It was incorporated as a town in 1810. The excellent water-power has been of great advantage in the developement of the city, as manufacturing is its chief industry, although it is located in an agricultural section. The canal has also contributed to the water-power available for manufacturing purposes. Its chief manufactures are paper, flour, beer, woolen goods, agricultural implements, machinery, tools, and iron. The trade is in the manufactured articles and in tobacco, hay, grain, and vegetables. The government is vested in a mayor, who holds office three years, and a board of control composed of five members, each one of whom is the head of a department of the city's government. They are elected for five years. The city owns and operates the electric light plant, the waterworks, and the gas plant. Pop. (1900) 23,914.

Hamilton, Ont., Canada, city and capital of Burlington Bay at the western extremity of Wentworth County, situated on the shores of Lake Ontario, 40 miles from Toronto, 42 miles from Niagara Falls, and 70 miles northwest of Buffalo. It was laid out and settled in 1813 by G. Hamilton, and is built on a plateau of slightly elevated ground extending around the front of a hilly range from Niagara Falls. Hamilton is connected with a large system of Canadian and American Railways, the Canadian Pacific, Grand Trunk, Toronto, Hamilton & Buffalo, the Michigan Central, the New York Central, and the Lehigh Valley and Wabash the head of Lake Ontario affords the best shipRailways. Hamilton's geographical position at ping facilities to the Northwest Provinces and European markets by water, while her railway facilities are not excelled by any city in the Dominion. She has also become a centre of a complete electric railway system. There are 60 miles of sewers, and 465 street electric lights. 19 miles of street railway, 110 miles of streets, Hamilton is the chief manufacturing city in Canada and is in the centre of a fine fruitgrowing district. It manufactures very largely, some of the chief industries being agricultural implements, air brakes, and electrical supplies, belting, boots and shoes, carriages, cigars, tobacco, clothing, drugs, elevators, emery wheels, engine packing, fertilizers, files, fireworks, furnaces, gasoline engines, harness, glue, mats, paints, pottery, soaps, spices, silverware, nails, wine, vinegar, mattresses, wringers, washing machines, and musical instruments. It has 2 cathedrals, 62 Protestant churches, 7 Roman Catholic churches, 15 banks, 18 public schools, 7 separate schools, 2 art schools, 2 convents, a public library, 26 charitable institutions, 4 hospitals, 2 incline railways, 4 theatres, a large insane asylum, 7 parks, a wireless telegraph station, 200 groceries, 5 bands, 2 sewage disposal works, 3 reservoirs, capacity (main) 11,000,000 gallons; 50 social and athletic clubs, about 200 national and secret societies, 100 hotels and 3 daily papers. Pop. (1904) 60,000.

J. CASTELL HOPKINS,

Editor The Canadian Annual Review of Public Affairs.

Hamilton College, an institution located at Clinton, Oneida County, N. Y.; founded by Samuel Kirkland, a Congregationalist missionary, in 1793, as an academy for both white and Indian children. The school was not opened until 1797. although Gen. Frederick William Steuben laid the cornerstone in 1794. Lack of funds prevented the completion sooner, and to the untiring efforts of its founder was due, in a great measure, the success of the undertaking. It was first called Hamilton Oneida Academy, so named in honor of one of its trustees, who was also a benefactor. In 1812 it was chartered by the University of the State of New York as Hamilton College. The school has grown steadily in facilities, keeping well abreast of the times. Two courses are offered: the LatinScientific and the Classical. It has fine scientific collections, an astronomical observatory, and well-equipped laboratories. The college has at its disposal fellowship, 55 scholarships, 4 prize scholarships (yielding $200 each), and a number of valuable prizes. The campus, nearly 100 acres, has many notable improvements, gifts from graduates. In 1904-5 there were connected with the school 18 professors and instructors, and 198 students. The library contained about 45,000 volumes. OREN ROOT, Registrar.

Hamilton Inlet, Labrador, the estuary of the Hamilton or Grand River (q.v.). It is 150 miles long and has a maximum width of 30 miles. On its north shore is Rigolet, a Hudson's Bay Company trading-post.

Hamilton, Mount. See LICK OBSERVATORY.

Hamilton Series, a series of rocks, including the Hamilton and Marcellus stages and constituting the middle Devonian. The name is from the town of Hamilton, 29 miles south of Utica, N. Y., where the series is typically developed. It consists there of shales and sandstones with a few beds of limestones, the most

prominent being the topmost member of the series. The Hamilton, like the other Devonian formations, was laid down along the Atlantic shores of what was then the American continent and in a great interior sea, sedimentation being heaviest in the northeast gulf of this sea. The sea extended from eastern New York to western Iowa. In the west the series is largely calcareous. The series is about 1,500 feet thick in eastern New York and reaches a maximum of 2.000 to 5,000 in Monroe County, Pa. It rapidly thins westward, and the south end of Lake Huron is only 20 to 50 feet thick. At the falls of the Ohio, above Louisville, the series is represented by 20 feet of hydraulic limestone. The rocks forming the high cliffs along the Delaware River south of Port Jervis, Pa., are of Hamilton Age. Outside of the interior basin rocks of Hamilton Age have been determined in the Gaspe region of Canada, where they reach a thickness of 7,040 feet. In the Eureka district, Nevada, is a great but undetermined thickness of Hamilton limestone, and in the Mackenzie River valley in Northwest Territory is a deposit of fully 500 feet of fossiliferous limestone, partly at least of Hamilton Age. From the fossils found it is evident that the plants in the Middle Devonian forests were mostly Acrogens and included giant club mosses or Lycopods, tree ferns and Equisetæ. One tree fern, Psaronius, had a trunk four feet thick. The gymnosperms were ancestors of the family of the conifers, being related to the yews. Insects, some of considerable size, abounded. In the ocean brachiopods were the most numerous and characteristic animals. Lamellibranchs were more abundant than in Cambrian time and there were true barnacles. The shallow muddy waters of the eastern part of the interior sea were not favorable to the growth of crinoids and corals, but these were common westward. Of the gasteropods Platyceras and Pleurotomaria were common genera. See DEVONIAN PERIOD; DEVONIAN SYSTEM and EQUISETÆ.