Page:Popular Science Monthly Volume 1.djvu/777

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constantly increase, and these will find much to satisfy them in Mr. Holley's book. He has collected a great deal of historical information in regard to its early observations, gives full descriptions of its aspects and surroundings, makes a very clear statement of its geological character, and enlivens the whole with anecdotes, accounts of accidents, adventures, escapes, and personal sketches of men variously associated with its history. The earliest printed description of the cataract is now nearly two hundred years old. It was made by Father Hennepin in the winter of 1678-'79, and is a curious mixture of sober truth and childish exaggeration. He says: "Betwixt the lakes Ontario and Erie, there is a vast and prodigious cadence of water, which falls down after a surprising and astonishing manner, insomuch that the universe does not afford its parallel. 'Tis true that Italy and Switzerland boast of some such things, but we may well say they are sorry patterns when compared with this of which we now speak. . . . It (the river) is so rapid above the descent, that it violently hurries down the wild beasts, while endeavoring to pass it, . . . they not being able to withstand the force of its current, which inevitably casts them headlong above six hundred feet high. This wonderful downfall is composed of two great cross-streams of water and two falls, with an isle sloping along the middle of it. The waters which fall from this horrible precipice do foam and boil after the most hideous manner imaginable, making an outrageous noise, more terrible than that of thunder; for when the wind blows out of the south their dismal roaring may be heard more than fifteen leagues off."


Bowlders of the Long Island Drift.—In a paper read before the Natural History section of the Long Island Historical Society, Mr. E. Lewis, Jr., gives an interesting account of the bowlders of the Long Island drift, treating especially of their size as compared with those of New England. On the north shore of the island, where the banks and headlands are rapidly wasted by the waves, bowlders, varying in size from a few inches to twenty feet in diameter, are thickly scattered about. Indeed, north of the central ridge of hills they are found everywhere, in some cases at an elevation of 300 feet above the sea-level. On Montauk Point, and in the neighborhood of the Hamptons, they are also abundant; and the immense deposits of sand along the southwestern shores were largely formed no doubt from bowlders and other materials of the drift, that have been ground up and deposited by the waves. This process is still going on, enormous quantities of bowlders and pebbles along the banks about Montauk being daily undermined and reduced to sand by the action of the surf. So far as observed, the bowlders are without sharp outlines, and many of them are exceedingly smooth. Those on the surface in the vicinity of Montauk have a blotched appearance, due to the presence of feldspar, and show evident traces of disintegration and decay. The excessive humidity of the air in this region is thought to contribute to this result.

Many of the bowlders are of large size, the largest being varieties of gneiss. Several have been carefully measured by Mr. Lewis. One on Strong's Neck, in Suffolk County, measures above the ground 22 by 26 feet, and is 25 feet high, giving a solid contents of about 14,000 cubic feet. At least half of this rock is believed to be below the surface. East of this are three masses of gneiss, which may have been originally one. If so, the volume of the mass could not have been less than 40,000 cubic feet; and if but two were originally united, of which there is reasonable certainty, the volume would have been about 27,000 cubic feet. Near Montauk are two masses of dark gneiss, one of which is, above the surface, 126 feet in circumference and 27 feet high, being somewhat cone-shaped. The other is about half this size. Not far from these is the finest though possibly not the largest specimen of gneiss upon the island. It is somewhat irregular in shape, compact in structure, and has a solid contents above the ground of 19,000 cubic feet. There are sections where bowlders, small and large, lie in masses that form continuous ledges.

The bowlders of Long Island, like those