a highly productive and populous valley, in which
limestone and hard timber are abundant. Its total
length is about one hundred and fifty miles.
The Maumee is the largest river in the northern part of Ohio. It rises in Indiana and flows north-easterly, into Lake Erie. About eighty miles of its course are in Ohio. It is navigable as far as Perrysburg, eighteen miles from its mouth. The other rivers north of the divide are all small, rapid-running streams, affording a large amount of good water-power, much utilized by mills and manufactories.
A remarkable feature of the topography of Ohio is its almost total absence of natural lakes or ponds. A few very small ones are found near the water-shed, but all too small to be of any practical value save as watering-places for stock.
Lake Erie, which forms nearly all the northern boundary of the State, is next to the last or lowest of America's "inland seas." It is 290 miles long, and 57 miles wide at its greatest part. There are no islands, except in the shallow water at the west end, and very few bays. The greatest depth of the lake is off Long Point, where the water is 312 feet deep. The shores are principally drift-clay or hard-pan, upon which the waves are continually encroaching. At Cleveland, from the first survey, in 1796, to 1842, the encroachment was 218 feet along the entire city front. The entire coast is low, seldom rising above fifty feet at the water's edge.
Lake Erie, like the others, has a variable surface, rising and falling with the seasons, like great rivers, called the " annual fluctuation," and a general one, embracing a series of years, due to meteorological causes, known as the " secular fluctuation." Its lowest known level was in February, 1819, rising more or less each year, until June, 1838, in the extreme, to six feet eight inches.
Lake Erie has several excellent harbors in Ohio, among which are Cleveland, Toledo, Sandusky, Port Clinton and Ashtabula. Valuable improvements have been made in some of these, at the expense of the General Government. In 1818, the first steamboat was launched on the lake. Owing to the Falls of Niagara, it could go no farther east than the outlet of Niagara River. Since then, however, the opening of the Welland Canal, in Canada, allows vessels drawing not more than ten feet of water to pass from one lake to the other, greatly facilitating navigation.
As early as 1836, Dr. S. P. Hildreth, Dr. John Locke, Prof J. H. Riddle and Mr. I. A. Lapham, were appointed a committee by the Legislature of Ohio to report the "best method of obtaining a complete geological survey of the State, and an estimate of the probable cost of the same." In the preparation of their report. Dr. Hildreth examined the coal-measures in the southeastern part of the State, Prof Riddle and Mr. Lapham made examinations in the western and northern counties, while Dr. Locke devoted his attention to chemical analyses. These investigations resulted in the presentation of much valuable information concerning the mineral resources of the State and in a plan for a geological survey. In accordance with the recommendation of this Committee, the Legislature, in 1837, passed a bill appropriating $12,000 for the prosecution of the work during the next year. The Geological Corps appointed consisted of W. W. Mather, State Geologist, with Dr. Hildreth, Dr. Locke, Prof J. P. Kirtland, J. W. Foster, Charles Whittlesey and Charles Briggs, Jr., Assistants. The results of the first year's work appeared in 1838, in an octavo volume of 134 pages, with contributions from Mather, Hildreth, Briggs, Kirtland and Whittlesey. In 1838, the Legislature ordered the continuance of the work, and, at the close of the year, a second report, of 286 pages, octavo, was issued, containing contributions from all the members of the survey.
Succeeding Legislatures failed to provide for a continuance of the work, and, save that done by private means, nothing was accomplished till 1869, when the Legislature again took up the work. In the interim, individual enterprise had done much. In 1841, Prof. James Hall passed through the State, and, by his identification of several of the formations with those of New York, for the first time fixed their geological age. The next year, he issued the first map of the geology of the State, in common with the geological maps of all the region between the Alleghenies and the Mississippi. Similar maps were published by Sir Charles Lyell, in 1845; Prof. Edward Hitchcock, in 1853, and by J. Marion, in 1856. The first individual map of the geology of Ohio was a very small one, published by Col. Whittlesey, in 1848, in Howe's History. In 1856, he published a larger map, and, in 1865, another was issued by Prof. Nelson Sayler. In 1867, Dr. J. S. Newberry published a geological map and sketch of Ohio in the Atlas of the State issued by H. S. Stebbins. Up to this time, the geological knowledge was very general in its character, and, consequently, erroneous in many of its details. Other States had been
