124 Analysis of Scientific Books. 
plain many ill-understood points of the mechanism and functions’ 
of the eye, and to renew our wonder at the properties of the organ 
itself, and the frame-work and apparatus by which it is suspended, 
moved, and protected. Mr. Bell concludes from his researches, 
that the high endowments which belong to this wonderful struc- 
ture depend not exclusively, as is generally conceived, upon the 
ball and optic nerve, but upon its exterior apparatus also. It is 
to the muscles, and to the conclusions, we are enabled to draw 
from the consciousness of muscular effort, that we owe that geo- 
metrical sense by which we become acquainted with the form and 
magnitude and distance of objects. It is impossible to do justice 
to Mr. Bell’s views in the short space to which we are obliged to 
confine ourselves in these abstracts: a careful perusal of the whole 
paper is absolutely necessary to those who would wish thoroughly 
to understand the investigation, and will amply repay even the 
more general reader. The author has shewn, by the most satis- 
factory illustrations, that we must distinguish the motions of the 
eye according to their objects or uses, whether for the direct 
purpose of vision, or for the preservation of the organ; that the 
eye undergoes a revolving motion not hitherto noticed; that it is 
subject to a state of rest and activity; and that the different con- 
ditions of the retina are accompanied by appropriate conditions of 
the surrounding muscles; that these muscles are to be distin- 
guished into two natural classes; and that in sleep, faintness, and 
insensibility the eye-ball is given up to the one, and in watchful- 
ness and the full exercise of the organ, it is given up to the in- 
fluence of the other class of muscles; and, finally, that the con- 
sideration of these natural conditions of the eye explains its 
changes as symptomatic of disease, or as expressive of passion. 
4, An Account of an Apparatus on a peculiar Construction for per- 
Jjorming Electro-Mugnetic Experiments. By W.H. Pepys, Esq., 
F.R.S. 
5. On the Condensation of several Gases into Liquids. By M. 
Faraday, Chemical Assistant in the Royal Institution, 
[Communicated by Sir H. Davy, Bart., P.R.S.] 
In this paper, Mr. Faraday follows up the train of investigation 
which the condensation of chlorine, by its own elastic power, so 
obviously opened.. Mercury and sulphuric acid were sealed up in 
a bent tube, and being brought to one end, heat was applied, 
whilst the other end was preserved cool by wet paper. The sul- 
phurous acid, which was generated, passed to the cold end, and 
was condensed i into a liquid. The properties of liquid sulphurous 
acid are as follow:—It is limpid’ and colourless; its refractive 
