Trans. N. Y. Ac. Scé. 82 Jan. 9, 
Hudson and Mohawk, and sweep the valley of the Mississippi to the 
basin of the Great Lakes. Rocks would be torn from their beds, and 
with all loose material, boulders, gravel, sand and clay, would be swept 
to and fro with overwhelming violence, and finally be spread far out 
over the bottom of the adjacent ocean. All this broad littoral zone, 
now crowded with life, and the scene of greater vital activity than any 
other equal area above or below the ocean level, would become at once 
a howling wilderness, where nature’s forces waged perpetual war, and 
lite would be impossible. 
So on all other shores, the physical and vital changes would be im- 
measurable. Erosion would be carried on with such energy that soon 
all continents would be worn away, all mountains be transported into 
the sea. All coral reefs, all sea-weeds, and indeed nine-tenths of all 
the lite on the globe, would, however, be swept out of existence before 
that time. Half the land of the globe would be submerged and deso- 
lated, and, with the destruction of the marine and the restriction to 
narrow limits of terrestrial vegetation, the pabulum of animal life would 
be so much reduced that the globe would be practically depopulated. 
It may also be said that if, as we suppose, the precipitation of ocean 
waters took place before the corrugations of the ear h’s surface had as- 
sumed any considerable magnitude, and it was nearly or quite covered 
with water, tidal waves 500 feet or more in he'ght, sweeping over the 
globe in rapid succession, would have worn away the emerging 
land as fast as it appeared, would have prevented the formation of 
continents and have precluded the existence of land animals or plants. 
From these facts, it will be seen that if such tides had been at any 
time in existence on the earth’s surface, traces of their action would be 
universal and indisputable. 
Having studied with some care the geological record in places where 
it is as nearly complete as anywhere, I must say that I not only fail 
to find any proof of the existence of these stupendous tides pictured 
to the imagination by Prof. Ball, but, on the contrary, the whole of that 
record, from the Archzan to the Tertiary, offers abundant and conclu- 
sive evidence against such a theory. 
As to what tock place before the deposition of the Laurentian strata, 
we can have no knowledge, because they are the oldest known rocks 
yet the era of their deposition can hardly have been Jess than twenty or 
thirty millions of years ago. Though much changed from their original 
condition as aqueous sediments, weare yet able to recognize in them the 
prototypes of the sandstones, shales and limestones of later formations, 
and we may fairly conclude that they were deposited under like condi- 
tions. In the gneiss and granite of the Laurentian we have representa- 
tives of the coarser sediments formed along shores; the slates are the 
