1882.] 
Analyses of Books . 
97 
upon the conic resistance which opposes its direcft descent, the 
divided parts having insufficient momentum of projection to 
move the lateral fluid tangentially. After the first division the 
divided parts again divide, and these again, so that by this con- 
stant division and subdivision the projected fluid takes a tree-like 
form.” In the author’s illustration accompanying this descrip- 
tion there appears, in faCt, a series of regular bifurcations. On 
repeating the experiment with the blue aniline ink we always 
use, the result was different ; the ink descended to the bottom of 
the trough in a long, very slender, thread, without any division 
at all. We then made several experiments with common black 
ink; we obtained results more like those figured by Mr. Stanley. 
There was division and re-division, sometimes into two, and at 
other times into three, branches. 
The author endeavours to trace a similar aCfcion in the organic 
world : — “ Such, for instance, as we find present in diffusion of 
liquids in the animal body, and the vegetable also under certain 
conditions ; possibly more especially in the early development, 
or setting out , as it were, of the circulatory system. The prin- 
ciple of diffusion here demonstrated may prevail in the formation 
of the circulatory system within animal tissues, — that is, assuming 
the animal to be at first in a fluid or semi-fluid state, formed of 
matter possible [? capable] of after coagulation to the set form 
we witness. The intrusion of blood or other liquid with small 
force would of itself, by the natural fluid forces here defined, 
open out, through any inequality of resistance or by a constant 
pressure in one direction, a reticulated system, which would not 
only be composed of canals for the future transmission of the 
fluids, but the forms of such canals would be the least fridtional 
for a constant flow through them afterwards.” 
In illustration, the author gives a microscopical view of the 
injecffed arteries of the bladder of the shrew, where bifurcation 
may in the main be recognised. The same form may, he con- 
tends, be traced in the veins of the liver, of the brain, of the 
mammary glands, and of certain tumours. This revival of iatro- 
mathematical speculation may be found worth a closer exa- 
mination. 
The author considers that plants have some power of engen- 
dering motive forces in the air for their own sustenance. 
We hope that the specimen given may induce scientific men 
to examine for themselves a work full of suggestions which must 
interest the geologist, the meteorologist, and the chemist. The 
author’s style is at times obscure, as may be seen from one at 
least of the passages we have quoted. 
