part of the country is so devoid of basins.  Its feeders drain the western slopes of the Alleghany and Cumberland Mountains—­Western Pennsylvania and West Virginia, representing sixty thousand square miles, the southern portions of Ohio, Indiana, and Illinois, and most of Kentucky and Tennessee.  These States are without lakes or ponds.  Nothing intervenes to hold back any portion of the vast flow from these coincidents of nature before spoken of, and therefore the excessive floods of last year and this.  Such results must continue to follow.

During the summer droughts the other extreme prevails.  For lack of a reservoir system to withhold and control the flow of water, the river falls from flood-tide—­seventy-one feet—­to points so low as to seriously impede or prevent navigation.  Sometimes even the smallest steamers and barges fail to pass between Pittsburgh and Cincinnati, and coal famines have not been unfrequent, resulting from difficult navigation.  An equable flow of this stream is impossible.  It will always be subject to these extremes.  Nothing but an extensive method of filling or diking is likely to prevent the inundation of cities and villages that are not seventy feet above low-water mark, with attending suffering and destruction of life and property.  All Southern rivers are liable to like extremes.

In contrast, it may be noted that the St. Lawrence River but slightly varies its flow, above Montreal, because of the restraining power of the Great Lakes, its feeders.  The upper Mississippi rises not to excess because of the thousands of lakes and lakelets in Wisconsin, Minnesota, and Dakota, its sources.  The floods occur in its southern portion, chiefly below St. Louis.  But for this reservoir system its navigation in the upper portion would be seriously impeded in summer seasons.

Disastrous floods can scarcely occur on the St. John’s, St. Croix, Penobscot, Kennebec, Androscoggin, Saco, Piscataqua, Merrimack, Connecticut, or Hudson Rivers, except from damming of the ice in winter or springtime (and that cause is of rare occurrence), such is the elaborate system of reservoirs about the headwaters of these streams.  This northern country is greatly benefited by these excavations occurring from geological causes.

The Merrimack River has a water-shed of about four thousand square miles miles—­one fiftieth part of that of the Ohio.  It has the Winnipiseogee, Squam, and Newfound Lakes, and hundreds of ponds to fill, that store a large amount of water, before any considerable rise can take place in the river, and then they restrain the flow.  No excess of water comes through the Winnipiseogee River, though it is the outlet of a water-shed nearly as great as of the Pemigewasset.  The freshets of the Merrimack come chiefly from the last-named stream and minor tributaries.  Without these reservoirs, the manufacturing establishments at Lawrence, Lowell, and Manchester, would cease to be operated by water-power during the summer droughts.  The highest flow of water in the Merrimack known in forty-six years, as measured at the Lowell dam, was thirteen and seven-twelfths feet.  This occurred in 1852.  Only a few times have freshets exceeded ten feet rise over that dam.