62 Notices respecting New Books. 
if it prove, which we do not doubt it will prove, as clear and syste- 
matic as the ‘ Physical Geology,’ it will furnish a welcome guide to 
those who may be dismayed at the size and cost of such a work as 
that produced by Dr. A. Geikie. If, however, one work leads up 
to the other, the success will be satisfactory, both to student and 
author. 
We might naturally expect to find Mr. Jukes-Browne more “at 
home” when he comes to deal with the succession of stratified roeks 
and their fossils, a subject reserved for his second volume; for he 
is perhaps best known to geologists through his successful labours 
among the Cretaceous and Post-Tertiary deposits. But a perusal 
of the present work enables us to speak in the highest terms of the 
wide research and full treatment of the subjects he has now brought 
before us. Illustrations are drawn from all parts of the world, and 
the author evidently gathers inspiration, as well as many duly 
acknowledged explanations, from the works of Lyell, Jukes, A. 
Geikie, O. Fisher, and other past and present leaders in Geology. 
Here and there we are disposed to differ in the use of terms or 
on theoretical questions. For instance, on p. 67 the author speaks 
of “the detrition of a district,” and ‘the denudation of fresh 
rock-surfaces,” when we should transpose the terms. Mr. Jukes- 
Browne strongly advocates the hypothesis that our Boulder-clay 
was chiefly formed by Coast-ice, or, in other words, that it was a 
marine deposit formed near ice-clad shores, but always under water. 
It has, however, not been shown that Coast-ice is capable of forming 
a comparatively uniform deposit of Boulder-clay spread over a wide 
area, usually devoid of any appearance of stratification, and con- 
taining no marine shells that lived on the spots where their remains 
are imbedded. It is true that the advocates of the formation of 
Boulder-clay by land-ice have to be equally guided by inference; 
but the frequent contortions and disturbances in beds underlying 
Boulder-clay, evidently produced by the agent which formed this 
glacial drift, seem to indicate a force more potent and extensive 
than coast-ice. 
Mr. Jukes-Browne has, however, taken pains to state the 
opinions opposed to those he may express or adopt; and we doubt 
not it will be some time before there is unanimity amongst geolo- 
gists on the subject of the formation of Boulder-clay. 
We should not omit to mention that Prof. T. G. Bonney con- 
tributes to this work a short chapter on “Original or Igneous 
Rocks.” The subject of rocks or of minerals cannot be made 
interesting, in the ordinary sense, to the student; nor for that 
matter can we say that the present volume is one to be read through 
lightly and easily by a general reader. But it is full of facts and 
information, and as such is just the work to be appreciated by the 
young and earnest student, who desires to learn about volcanoes 
and earthquakes, springs, the formation of various deposits, the 
structure of rocks, and the origin of hill and valley, mountain, lake, 
and river. 
