Page:Popular Science Monthly Volume 68.djvu/306

carrying devastation before them like the waters from cloud-burst or bursting reservoirs of to-day, but on a thousandfold larger scale. By this bursting all the country on both the Canadian and Fredonian sides must have been drained and left bare, exposing to view the water-worn pebbles, and the whole exhibition of organic remains there formed. Great masses of primitive rocks from the demolished dam, and vast quantities of sand, mud and gravel were carried down the stream to form the curious admixture of primitive with alluvial materials in the regions below.

A fresh contribution to the subject was rendered this same year, in the publication of Amos Eaton's 'Index to the Geology of the Northern States.' Eaton's views were in part, at least, a reflection of those of Werner. We have to do here, however, only with that portion of the work relating to the so-called alluvial class of rocks. In discussing this and attempting to account for the great masses of granite and syenite which he found scattered throughout the Connecticut River region, he wrote:

What force can have brought these masses from the western hills, across a deep valley seven hundred feet lower than their present situation? Are we not compelled to say that this valley was once filled up so as to make a gradual descent from the Chesterfield range of granite, syenite, etc., to the top of Mount Tom? Then it would be easy to conceive of their being rolled down to the top of the greenstone where we now find them.

It was not easy in all cases for the geologists of these early days to distinguish between the younger and earlier drift, or between the material which we now consider as glacial drift and the loosely consolidated alluvial deposits of the Tertiary period. This seems particularly true of Dr. H. H. Hayden, a Baltimore dentist and one-time architect, who in 1820 published a volume of geological essays in which he dwelt very fully upon the lowlands, or the area at present comprised within the so-called Coastal Plain. After referring to the geographical limits of this plain and combating the opinions of previous observers, he elaborated his own theories somewhat as follows:

Viewing the subject in all its bearings, there is no circumstance that affords so strong evidence of the cause of the formation of this plane as that of its having been deposited by a general current which, at some unknown period, flowed impetuously across the whole continent of North America in a northeast and southwest direction, its course being dependent upon that of the general current of the Atlantic Ocean, the waters of which were assumed to have risen to such a height that it overran its limits and spread desolation on its ancient shores.

In seeking the cause of this general current Hayden referred first to the seventh chapter of Genesis:

For yet seven days and I will cause it to rain upon the earth forty days and forty nights, and every living substance that I have made will I destroy from off the face of the earth.

He then proceeded to show the inadequacy of rainfall alone, since the water being thus equally distributed over the ocean and the