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THE VETERINARIAN, MAY 1 , 1833 . 
Ne quid falsi dicere audeat, ne quid veri non audeat.—C icero. 
ON THE EXTERNAL CAUSES OF DISEASE. 
[Aerial Poisons, &;c. continued from page 135.j 
WE concluded our last paper by stating that the blood was 
possessed of vital properties, and that, in all diseases arising 
from aerjal poisons, it was contaminated.” The vital properties 
of the blood were suspected by Hippocrates : Harvey and Hunter 
firmly believed and taught it; and on considering the subject, 
it does appear extraordinary that the vitality of the fluid part of 
an animal body, which constitutes about five-sixths* of its weight, 
should ever have been doubted, much less denied. 
The liquids constitute not only, the greatest part of the body, 
but they actually existed before the solids were in being, as the 
embryo, which is at first in a gelatinous state, may be considered 
as a fluid. 
Again ; the solids are not only formed from the liquids, but it 
is by the latter that all the organs receive their nourishment, and 
repair their waste. 
“The blood the fountain whence the spirits flow, 
The generous stream that waters every part. 
And motion, vigour, and warm life eonveys. 
To every particle that moves or lives.'' 
Again; the solid matter of which a living body is composed 
is in a state of continual change; old and worn out particles are 
every moment taken up from their station, and carried out of 
the system, and new particles are every moment conveyed to the 
place occupied by the old and deposited in their room: thus, 
solidity may be considered as only existing in a transient state, 
or, as Richerand expresses it, "" an accidental state of organized 
living matter,” since the solids formed from the liquids return to 
their former state, when, having for a sufficient length of time 
* Richeiaud. 
l1 
voL. vr. 
