250 
ON THE PATHOLOGY OF CATTLE. 
1.850, .835 and 1, or 1.850, .835 and 1000, or .850 grains heavier 
than water, and .165 grains lighter than water. Proof spirits 
are five parts of sp. rectif. 56° over proof by Sykes’ hydro- 
meter at the temperature of 62° Fahr., and three parts of 
aqua distillata mixed. There are several hydrometers and sach- 
arometers in use for taking specific gravities which we need 
not describe, as books and tables are sent with them. Sykes’s 
are the only ones recognized by the revenue laws : also we have 
acidometers, urinometers, nitrometers, hydrostatic beads, See. 
The competition at present in the chemical and drug trade is such 
that a genuine article is difficult to be procured ; hence, the medical 
practitioner is disappointed of the effect of the medicine admi- 
nistered. The result invariably is, that obloquy is brought on his 
practice and medicine. The chief object of this paper is to point 
out to those concerned, who, perhaps, have not thought much on 
the topic, the manner of taking the specific gravities of their 
chemicals and drugs : if that is done, and by comparing them with 
the specific gravities published in tables, they will be enabled to 
judge of their quality and value to a great extent. 
I have to acknowledge my obligations to Geo. Townes, Ph. D., 
and Mr. Redwood, for their papers on Specific Gravity. 
ON THE PATHOLOGY OF CATTLE. 
By G. Baker, Esq., M.R.C. V.S. 
My dear Sir, — Assured of the great interest you take in the 
nature and classification of diseases of cattle, 1 feel much satisfac- 
tion in transmitting to you a case which is certainly, in my opinion, 
of unusual occurrence. 
During one of my professional visits to a gentleman in Sussex, 
while attending a horse, he asked me to accompany him to his 
farm yard, having the previous day lost a cow, and which the man 
was going to take to the kennel for the hounds. It appeared that 
some few months since she was the subject of a severe attack of 
the then prevailing epizootic, but had recovered under the treat- 
ment of some cowleech of good repute in the neighbourhood. She 
was in apparent health when seen in the evening, but found dead 
in the morning. 
Being curious to ascertain, if possible, the cause of this sudden 
and fatal result, I was but too happy to offer my services in the 
post-mortem inquiry. On examination of the abdomen, the viscera 
generally were in a healthy state ; but, on prosecuting the investi- 
gation in the chest, l found that the right pleural sac contained a 
