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CENTRAL VETERINARY MEDICAL SOCIETY. 
to this malady and some other disorders of the nervous centres. 
Hering studied it in its physiological condition. The cerebrum 
and cerebellum being in close proximity to the cranial walls, not 
much room is left for this fluid; but round the medulla oblongata 
and spinal cord, where a comparatively large space exists, a 
considerable quantity of the fluid is met with. In order to ascer¬ 
tain the relative distribution of this fluid within the cavity of the 
cranium, a horse was killed, and the roof of the atlas with that 
of the cranium removed by mallet and chisel, the end of the 
medulla external to the "dura mater being tied. The head was then 
exposed to a freezing mixture, and afterwards opened, when it 
was noticed that around the medulla oblongata and cerebellum, 
between the dura mater, and arachnoid there were flakes of ice, 
weighing from 90 to 120 grammes, and small flakes within the 
ventricles of the cerebrum, while the frozen fluid surrounding 
the spinal cord was found to weigh 400 grammes. This fluid 
under ordinary conditions exists in a closed sac between the mem¬ 
brane, and is not influenced by gravitation, hence it is most pro¬ 
bable that an inordinate quantity in any part would occasion 
serious compression. The quantity of fluid the spinal sheath 
contains cannot be easily ascertained when an incision is made 
during a post-mortem examination, as the fluid is only thereby 
partially removed. Hering also observed that the quantity 
diminishes gradually after death, the cerebral or medullary sub¬ 
stance appearing to absorb it, hence the difference in the results 
quoted by different authors. Renault, Leisering and others, 
estimates the quantity at 120 to 430 grammes in healthy horses. 
Supposing, therefore, the normal quantities to be as stated, and 
it is not known that they exceed this amount, it was a mistake to 
suppose that so-called “ Immobility” was due to compression of 
the nervous centres, in or around the brain, for as the sheath was 
continuous therefrom, such pressure would also influence the 
functions of the cord, which is not the case. 
Mr. Clarice reported several cases of spinal apoplexy in mares, 
caused, he believed, by the recent hot weather. One case had 
followed another attended by rapid decomposition after death. 
The post-mortem examination showed serous effusion, but no 
ecchymosis. 
The President intimated that on an early occasion he would 
call attention to a disease now prevalent amongst horses on the 
Continent of Europe, and in Algeria, as yet unknown here, bear¬ 
ing some resemblance to syphilis of man. 
Mr. J. P. Cox related a case of a cancerous disease of the tibia 
of a dog. The animal—a mastiff—was a great favourite, and 
expense of treatment of no importance. The external appearance 
of the part was that of a simple tumour. He proposed to remove 
