January 8, 1914] 
NATURE 
Jot 
and metamorphic rocks; in the second place, we 
have ‘“lava-cones” built up entirely by outwelling 
streams of liquid rock from a fissure; and, 
thirdly, ‘composite cones” built up by alternating 
ejections of fragmental materials and_ lavas. 
The varied slopes of cones, as determined by the 
nature of the fragmental materials or the degree 
of liquidity of the lavas, are well explained and 
illustrated. The very graceful forms assumed by 
some voleanoes—which is so conspicuously illus- 
trated by the representation of the famous 
Japanese mountain Fujiyama—are explained by 
the author as being due to the larger ejected 
fragments accumulating nearest to the crater, but 
it may be in part also due to central subsidence. 
Such subsidence is admitted by the author to have 
Photo.) 
Fic. 2 —Mount Rainier (or Tacoma), Washington, U.S.A. 
An extinct conposite voleano—snov capp2d and supporting glaciers. 
from the ocean-floor to a height of 30,000 ft., 
while, so- gentle are their slopes, they have 
diameters of more than 80 miles. At the 
‘other end of the scale, and as a supplement to the 
catalogue of volcanic mountains, 
and mud-volcanoes (“air 
author) are noticed. 
In contrast to the elevations produced by the 
heaping up of materials brought from below the 
earth’s surface we have “epigene types,” formed 
by superficial detritus piled up either by glacial 
or eélian agencies. To the former class belong 
moraines of all kinds—sometimes forming’ hills 
more than 8o0o ft. in height-—with the less con- 
spicuous but more extended terrestrial features 
known as drumlins and eskers. As the result of 
geyser-cones 
volcanoes” of the 
[Detrozt Pub. Co. 
From “ Mountains : ;' 
their Origin, Growth, and Decay.” 
taken place in the formation of some volcanic 
craters like that of the celebrated “Crater-lake ”’ 
of Oregon. The results of denudation on volcanic 
cones is well illustrated. In describing the 
manner in which younger volcanic cones rise 
within old craters, the author unfortunately 
speaks of “cone-in-cone ” structure, a term which 
has already been appropriated by geologists for 
a totally different phenomenon. As _ illustrating 
the vastness of the agencies by which volcanic 
mountains are built up, the author justly points 
out that the great cones of the Hawaiian Islands 
must be regarded as the grandest orographic 
feature on the globe, seeing that these cones rise 
NO. 2306, VOL. 92] 
wind-action, we have the sand dunes of sea- 
coasts and the far more extensive structures of 
the same kind characteristic of deserts. ~ 
In passing from the comparatively simple 
“mountains of accumulation” to the opposite 
| class, to which he gives the name of ‘deformation 
mountains,’” our author approaches, as he him- 
self admits, the most difficult part of his task. 
He commences by giving an outline of the his- 
tory of the development of our knowledge of the 
subject, in which he justly lays stress on the 
important effect of Lyell’s protest against the 
orographic theories of de Beaumont; and he goes 
on to indicate the value of the subsequent work 
