, 
REVIEWS AND BOOK NOTICES. 161 
extended as far as the materials were accessible, such as the re- 
sults of the deep sea soundings made by the Hydrographic bureaux 
of the European and American governments, to the pr incipal seas 
of the globe. It is of course more complete for the seas border- 
ring on France, yet it is a fair beginning of a subject which hith- 
erto has received but little attention. The author has treated his 
materials ‘with great success and has sketched out the broad out- 
lines of a most fruitful line of inquiry. 
It is the first systematic attempt made to classify the Jenoa 
now going on owing to the agencies at work on the surface of our 
earth; to show how unequally the deposits are made, how greatly 
the nature of these deposits and the existing topography are modi- 
fied by the direction of the prevailing winds and oceanic currents, 
and more especially how materially the geology of the shores of 
the river basins, and of submerged rocks subject to the action 
of the waves, influences the mineralogical constituents of the de- 
posits formed at any one point. 
The maps which accompany this volume are the results of the 
most careful examination and analysis of the materials brought up 
by the lead, or thrown on the shores by the action of the waves, or 
resulting from the decomposition of the cliffs along the coast line, 
of the banks of the rivers forming the different hydrographic basins, 
from their source as they pass through the different geological for- 
mations to their mouth. The fate of the different mineralogical _ 
constituents is carefully followed and the effect each has upon the 
bottom of the sea into which the basin drains carefully noted. 
The effect of the atmosphere in carrying dust in suspension, of 
the direction of the prevailing winds, especially on the seacoasts 
leading to the formation of dunes, and the effect produced by the 
unequal distribution of rain as an erosive agent in the different 
hydrographic basins are very accurately considered. The amount of 
material held in solution and suspension in the rivers of France is 
shown to be enormous and to depend of course mainly upon the 
geological composition of the rocks of the different hydrographic 
basins influencing, to a great extent, the condition of the naviga- 
tion of the outlets of the larger rivers, and the formation and 
preservation of the harbors at the mouth of the navigable rivers. 
The power of transportation and erosion of fresh water and rain 
as shown by the action of rivers, is slight compared to the action of 
the sea; the SPRER, results prone by waves, by permanent 
ani. NATURALIST, VOL. VH. 
» 
