Monthly Mlcroscoplcan 
Journal, Sept. 1, 1869. J 
( 165 ) 
PKOGEESS OF MICKOSCOPICAL SCIENCE. 
The Structure of the Cerebral Hemispheres. — On this subject a paper 
of considerable length was taken as read at the last meeting of the 
Eoyal Society, and will appear at length in the forthcoming number of 
the ' Proceedings.' The paper was by Dr. W. D. Broadbent. The 
object of the investigation was twofold. First and chiefly, to en- 
deavour to ascertain minutely the course of the fibres by which the 
convolutions of the hemisi^here are connected with each other and 
with the crus and central ganglia. Secondly, to endeavour to ascertain 
whether there is a constant similarity between the corresponding sides 
of different brains as compared with the opposite sides of the same 
brain ; and should this be the case, to endeavour to trace the relation 
between any anatomical difference which might be discovered and 
such physiological difference as seems in the present state of our 
knowledge to be indicated by the association of loss of the faculty of 
language with disease of the left hemisphere rather than the right. 
Dr. Broadbent's paper relates almost exclusively to the first branch 
of the investigation, and the rqethod pursued has been to harden the 
brain by prolonged immersion in strong spirit, by which the fibres are 
rendered perfectly distinct and fairly tenacious, so that with care 
and patience their course and arrangement may be accurately ascer- 
tained. Previous researches on the structure of the cerebrum have 
been mainly directed to the examination of the course and distribution 
of the fibres radiating from the crus and central ganglia, which have 
been assumed or supposed to occupy ultimately the axis of every con- 
volution, the different convolutions being connected by fibres which 
crossed under the sulci from one to ant)ther. In this paper of Dr. 
Broadbent's it is shown that tlje commissural communication between 
different parts of the hemisphere is much more extensive than has 
hitherto been described, and that the fibres more commonly run longi- 
tudinally in the convolutions than cross from one to another, while 
large tracts of convolutions have no direct connection with the crus, 
central ganglia, or corpus callosum. The details of the paper are too 
numerous for reproduction here. 
Photo-micrography applied to Class Demonstrations. — Colonel Dr. 
Woodward, of the United States Army, recently [May 81st] de- 
livered a lecture on this important subject before the Biological and 
Microscopical Section of the Academy of Natural Sciences of Phila- 
delphia. A very long abstract of the lecture is published in the 
American ' Dental Cosmos ' for August, and from this we take the 
following account : — The lecturer, after stating that it was found to 
be impracticable, if not impossible, to exhibit, with any satisfactory 
degree of correctness, to a large class or assemblage, such microscopi- 
cal preparations as require the use of high powers, even though aided 
by the oxyhydrogen or other powerful lights, explained how his atten- 
tion came to be given to photo-micrography. The great field promised 
by the pursuit of this branch of microscopy had already induced some 
