TUMOUR WITHIN THE CRANIUM. 
149 
he was plunging about the stall, and knocking his head 
against the wall ; the breathing was very laboured, and the 
body covered with perspiration. From the first, Mr. Spooner 
was convinced it was a hopeless case, and despite all his 
remedial measures, after a most desperate struggle, the animal 
threw himself backwards and died . — {See Abstract of Proceed- 
ings, Session 1838-9.) 
But we have said that these formations involve an interest- 
ing chemico-physiological inquiry. In their composition they 
resemble the brain itself to a certain extent ; there being that 
remarkable fatty substance in them called cholesterine, with 
albumine, and phosphorus combined with lime. “ The most 
important point in the chemical history of the brain,” says 
Dr. Gregory, i: is that it contains both fat and albumen, the 
two extremes of the animal products ; and substances — cere- 
brie and oleo-phosphoric acids— of a composition intermediate 
between that of albumen and that of fat. These bodies, how- 
ever, appear to contain even a larger proportion of phosphorus 
than albumen.” From the abnormal action set up, has there 
taken place the formation of the sub-phosphate of lime instead 
of these peculiar acids ; thus giving to the mass its granular 
character, and at last rendering the brain unfit to carry on its 
all-important functions, when the tumour has attained such a 
size as to communicate pressure to it ; before which no indica- 
tions of its presence are manifested from the progress of this 
deposit being so exceedingly slow ? 
These accumulations of cholesterine sometimes take place 
in a very peculiar manner. We have in our possession the 
cerebellum of a mare, in which they are arranged at intervals 
upon the plexus choroides of the fourth ventricle, in the 
form of small globular-shaped masses, resembling beads on a 
string : and each one having the characteristic lustre of this 
principle, gives to the specimen a still greater resemblance to 
these so-called ornaments. The animal, from which it was 
taken, died after a few hours 5 illness, which was ushered in by 
convulsions, an incapability of standing, and quickly followed 
by paraplegia. She was a well-bred animal, the property of 
a gentleman, who used her in his park phaeton, and he 
frequently complained of the difficulty he experienced in 
holding in while driving her, from the excited state she often 
suddenly evinced in her work. Similar symptoms of excita- 
bility were occasionally observed by the groom when the 
animal was in the stable. These, however, were referred to 
her high breeding, and an irritable temperament ; but they 
were doubtless depending on this deposition of cholesterine 
on the vessels of the brain. 
