Review of Recent Geological Literature. 397 
produced by a powerful submarine earthquake, show that no such wave 
has swept upon that coast since the Glacial period. ( >n Long Island and 
south to Florida the extensive beach ridges of sand, separated from the 
main shore by long and shallow bays and sounds, arc also shown by 
Prof. Shaler to indicate similar long immunity from earthquake sea* 
waves. Likewise through large regions in the interior of the United 
States, the occurrence of delicately poised boulders, and, south of tin- 
drift area, the unstable rock-cliffs and columnar or tower-like rem- 
nantsof eroded strata, and insecurely pendent stalactites in caverns, tes- 
tify of long quietude, unbroken by earthquake shocks, at least during the 
"ten thousand years or more" since the Ice age. w. r. 
The Geographical Development of Alluvial River Terraces. By II. E. 
Dodge. (Proc. Boston Soc. Nat. Hist., vol. xxvi, pp. 257-273; June, 1894.) 
The processes of fluvial deposition and subsequent erosion, leaving rem- 
nants of old flood-plains as terraces on the sides of the river valleys, are 
hen; reviewed, with consideration of the geographical cycle and devel- 
opment of a normal river, and a classification of alluvial terraces ac- 
cording to the variable conditions of their origin. In glaciated regions 
the abundant stream terraces of stratified gravel, sand and clay have 
been sculptured, and in large part redeposited again and again, from the 
original flood-plains supplied by the drainage of the ice-sheet during its 
departure at the close of the Glacial period. The Connecticut river val- 
ley, rendered classic by the early work of E. and C. H. Hitchcock for 
the geological surveys of Massachusetts and Vermont, and later more 
fully described in its northern part for the survey of New Hampshire, 
lias along most of its course two, three, four, or more of these terraces 
on one or both sides of the riser. Usually drift-bearing countries have 
undergone some differential elevation since the weigh! of the ice was re- 
moved, and each terrace is thought by the author to show a temporary 
level of the stream during a lime of rest or slackening of the uplift, 
while the escarpments or steep fronts of the terraces are regarded as 
evidence of intermittent stages when the upward movement was more 
rapid, causing the streams to cu1 down their channels. w. r. 
Tin Preglacial Channel of the Geneset river. By A. W. Grabau. (Pro- 
ceedings, Boston Soc. Nat. Hist., vol. xxvi. pp. 859-369, with map; 
read May Hi, 1894.) The Genesee river above Portageville, X. Y.. Hows 
in a broad preglacial valley. Next the river has cut a narrow and very 
picturesque rock gorge for about 25 miles to Ml. Morris. Again it Hows 
thence nearly to Rochester in a large pveglacial channel; bu1 in the cit\ 
of Rochester it a second time enters a deep postglacial rock gorge, seven 
miles long, descending into ii with three falls. Above Mt. Morris the 
second broad valley is occupied by the Caneseraga creek-, and farther 
west the Oatka creek, another tributary of the Genesee, runs in a paral- 
lel preglacial valley. The connection of these valleys with their proba- 
ble preglacial continuation along the [rondequoit river and baj (des- 
cribed in the a.m. Geologist, vol. v, pages 202-307, with map. April, 
