Davis.] 
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[January 18 , 
erosions (not farther explained), (d) clefts ; second, proximate 
or incidental, the effect of (a) glacial action, (b) subsequent 
eruptions, (c) drift, (d) damming by drift-wood, (e) beaver dams, 
(f) irregular subsidence or elevation. There are areas of numerous 
lakes, but it is not well determined why — perhaps because they 
are new lands; and areas of no lakes, where the barriers are 
worn down. In composition : fresh, having overflow, in northern 
regions that have been glaciated, but relation of effects to cause 
has not been clearly set forth ; salt, in dry regions, no overflow. 
ISTo examples by name. This paper as published seems too con- 
densed to do justice to its author. 
Jukes and A. Geikie. Manual of Geology, Edinburgh, 1872, p. 
460. Most lakes are in rock-basins, and in northern parts of the 
globe, in greatly denuded regions; basins are of recent origin. 
They are found first, behind barriers of superficial accumulations, 
(a) gravel from side stream, (b) land slips, (c) moraines, (d) irreg- 
ular deposits of detritus as (1) among morainal mounds, (2) 
among dunes, (3) on drift or boulder clay, (4) between volcanic 
cones, (5) in craters, maare , (6) lava dams. Second, in rock 
basins formed (a) by depression of upper part of valleys (suggested 
but not admitted), (b) by local subsidence as Dead Sea and per- 
haps lakes of Central Africa, (c) by sinks, as turloughs of Gal- 
way, (d) by ice erosion, for the vast majority of lakes in the 
Northern hemisphere. 
A. Geikie. Elementary lessons in Physical Geography, London, 
1879, 265. Less explicit than the above, being adapted to younger 
students. Lakes occur in inequalities in the land surface ; many 
in northern Europe and America ; basins in rock, in superficial 
detritus, behind moraines, in depressions orv table-lands, many of 
these being salt, maritime lagoons, sinks. Examples of size, depth 
temperature, and effect on rivers. 
Huxley. Physiography, New York, 1878. Lakes are given 
only a short geographic description. 
Dana, in his Text-book and Manual of Geology, treats lakes 
only incidentally: in the latter, edition 1880, p. 842, is a list of 
nine causes of lake-basins, in half a page, under the heading 
“ Effects referred to their Causes.” 
Peschel. Physische Erdkunde, edited by Leipoldt, 2 v. Leip- 
zig, 1879-1880, ii, p. 313. The chapter on Lakes is taken with 
