132 PROCEEDINGS OF SOCIETIES. 
Mr. Warineton described some additions which he had 
made to his portable microscope, by which living objects 
contained in glass bottles or small aquaria could be examined 
with greater ease. 
Mr. C. Brooks exhibited a microscope and case very com- 
pletely fitted up, but having a stand of so simple and light a 
character as to render it very portable and easily worked, even 
in the open air, at the seaside or elsewhere. 
Mr. Lapp exhibited a microscope with an improved mag- 
netic stage. The improvements in the structure of the 
microscope exhibited by these instruments were commented 
on by several speakers. The facility of moving objects deli- 
cately by the hand, afforded by the magnetic stage, was 
remarked upon as a great advantage. Mr. Brooke’s imstru- 
ment was fitted with a double lens, so that the power could 
be changed from a high to a low one without unscrewing the 
glass, and was regarded as an improvement that ought to be 
more frequently employed in the construction of microscopes. 
September 28th, 1858. 
Section A. 
On a New Law of Binocular Vision. 
By the Rev. J. Drnexz. 
Tue object of the law in question is to obviate the imper- 
fect vision which would sometimes arise from the difference 
of the pictures in the two eyes. In some cases this difference 
would lead to great inconvenience and confusion. It some- 
times happens, for instance, that m looking at a field of view 
at some distance, objects considerably nearer are so interposed 
as to present themselves in the picture formed in one eye and 
not in the other. Thus, in looking at a landscape, if the 
finger or any other object is held before one eye, the image 
of it from the one retina is superposed in the sensoriwm on a 
part of the landscape formed in the other eye. On mere 
physical principles, this might be expected to blot out or 
greatly confuse that part of the landscape upon which it was 
placed; but upon trial this is not found to be the case, as 
that part is merely a little dimmer than the rest from being 
seen only with one eye, but is equally distinct and as truly 
coloured. By various experiments the author had ascertained 
that this was the result of a peculiar power of the will, by 
means of which the mind is enabled, when two different 
images are superposed in the sensorium, to select whichever 
it pleases, to bring that object into view, and entirely to 
