400 Recent Literature. [April 
banks.” Here again the inquiry arises, How could these tumultu- 
ous, “ unimaginable floods ” have poured southward “ without ces- 
sation” if the ice-sheet was so thin and meager as Mr. Lesley 
imagines? The hyper-cataclysmal language here used for one 
series of phenomena, the result of a melting of an ice-sheet which 
was merely thick enough to “polish off” the: topography ofa 
continent, appears somewhat illogical and extreme. Should it 
not apply to the ice-mass as well? Farther on, to account fr 
“vast heaps of rounded boulders” and other drift deposits onthe 
tops of crests, ridges and hills at elevations of near 1000 feet i 
the counties above named, the director of the survey remarks: 
“ It seems to me necessary to suppose some sort of submergence 
of the region beneath sea-level, or, what will amount to the same 
thing, a general rise of ocean-level to 800’ or 1000’, A. T. 
would flood all Southeastern Pennsylvania to within a few hur 
dred feet of the crests of its mountains, and account for most of 
the terrace deposits in this region.” i A 
While Northeastern New England has evidently been 
merged some 500 feet, as marine fossils clearly indicate, are re 
any facts which show that this submergence extended much, 
any, below New York city? We have supposed that ae 
this point the oscillation of the coast line was confined to Qut 
few feet, as witnessed by the position near sea-level of the | 
tions as have been brought up in the present able report. 
Seconp Report or THE U. S. GEOLOGICAL SURVEY. — ee 
this report has been issued for some time it has not bet priate? 
in this magazine. It is a bulky royal octavo volume, } as (f 
on good paper, with excellent and abundant ile axeciti@ 
one plates and thirty-two wood-cuts); the mechan ee 
being much superior to the average Government | geology 
more notable contents are the reports on the physice onion 
the Grand Cañon district by Capt. C. E. Dutton, » 
to the history of Lake Bonneville, by G. K. rege 
a report on the geology and mining industry of Comstock 
F. Emmons; a summary of the geology of the oduction of 
and the Washoe district, by Geo. F. Becker; Pf King; 2 
precious metals in the United States, by Ca 
method of measuring heights by means of the oo 
K. Gilbert. the Grand @ 
The splendid report of Captain Dutton on ae our Di 
district having been published in full, we shall dete E 
1 Second Annual Report of the United States Geological Survey æ 
81r. By 
7 1882- 
the Interior, r880~' 8r J. W. POWELL, director. Washing! l 
8vo, pp. 588.. 
