’8 
POPULAR SCIENCE* REVIEW. 
stately forests, and poplars and plantains grew where now the fugitive 
summer scarcely gives birth to a few stunted herbs in particularly favoured 
situations.” At this time Central Europe enjoyed a sub-tropical heat, and 
huge salamanders, tortoises, and apes were to be found abundantly. If we 
had space we should add another paragraph, on the subject of aerial ma- 
chines, balloons, &c., which are most intelligently detailed, but we cannot. 
We see only one fault, and that, unfortunately, is in a book in which aerial 
travelling should have occupied a very large share of the author’s attention 
—viz. that the subject of aerial navigation has been but imperfectly studied. 
The author does not appear to have been acquainted with our Aeronautical 
Society, and hence he has not read any of the several treatises that have 
been published by Mr. Wenliam, and other members, upon the scientific 
grounds on which those who wish to work toward a practical end must 
necessarily labour. We trust to see this defect repaired in a succeeding 
edition; for although one of Mr. Glaisher’s first trips is described, that is by 
no means exhaustive of British efforts. Still the book is, as we have already 
said, most creditable to its author, most interesting to the public, and, in 
illustration and topography, it is everything that could be desired. 
ECONOMIC GEOLOGY* 
I T seems to us that Professor Page has hit upon a new vein in the present 
work, and one, too, which cannot fail to promote an extension of the 
arts and manufactures ; while, if we look merely to the sale of his book, 
we may, in an anticipatory fashion, congratulate the publisher upon 'its issue. 
We say so because we are certain that, in setting himself to work at the 
field, he has now explored, the author has rendered the ordinary journey of 
the worker infinitely shorter than it used to be. He has spared him that 
species of encyclopaedic travelling wdiich is at once so lengthy and so fre- 
quently unsatisfactory. We know of nothing in the shape of an English 
work in which the man who is working at geology can find the information 
which in the present book is clearly set out before him. And by the worker 
we by no means infer “ the gentleman with the hammer,” who is simply 
intelligently amusing himself during the summer vacation. We refer to the 
man who, whether he be an agriculturist, or an engineer, or an inspector of 
mines, or a glass or china manufacturer, or a whetstone-maker, or a searcher 
after mineral springs, is engaged in a careful study of the soil, to endeavour 
to obtain from it the particular rocks or liquids which are of importance in 
his trade. A careful student of Lyell, or Phillips, or Murchison, Jukes, or 
Ansted would fail utterly in the peculiar knowledge demanded by any one 
of the above. Yet it is exclusively such men as these, who are in search of 
the mines or other mineral products, who are unquestionably the makers of 
the immense wealth which this country possesses. Mr. Page has thus 
* u Economic Geology; or, Geology in its Relation to the Arts and 
Manufactures.” By David Page, LL.D., F.G.S., Professor of Geology in 
Durham University, College of Physical Science, Newcastle-on-Tyne. 
Edinburgh : Blackwood & Sons, 1874. 
