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YORKSHIRE VETERINARY MEDICAL SOCIETY. 
nature, the one from the other; but as to that, is it not patent to 
every thinking man, that almost every epizootic and enzootic, as 
well as every epidemic and endemic, are dependent upon causes 
utterly distinct, and different from one another? The virus or germ 
that produces influenza will not produce glanders, and vice versa , 
the virus or germ that produces cattle plague will not produce 
pleuro-pneumonia, and vice versa. The virus or germ that produces 
either smallpox, yellow fever, cholera, scarlatina, &c., will produce 
only the specific disease it is destined to produce. 
We will now suppose we have a case of chest influenza. The 
horse has been living in a stable in which the air is humid and 
confined; it is replete with putrid matter floating in the air, though 
indistinguishable. I will not say whether the particles are organic 
germs or virus poison, but I can easily conceive their effects to be 
of an acrid, caustic, inflammatory nature; and being inhaled, 
they adhere to and irritate by contact the delicate lining 
membrane of the air-cells, as definitely and as certainly as the 
inevitable effects of a nettle upon the hack of the hand, the sting 
of a wasp upon the forehead, or the effects of scalding steam 
upon the skin. This is instantly followed by irritation, tur- 
geseence takes place to a greater or less extent, according to the 
intensity or mildness of the attack,—and this I hold is dependent 
upon the proportion of the deleterious matter in the air. At this 
stage the excitement in the lungs may readily be calmed' and 
soothed, by at once placing the patient so that he must inhale pure 
and fresh air, and administer to him diffusible stimulants. At 
this particular point of my subject, there arises a most vital and 
deeply interesting question. I would call it a difficult physiological 
problem : 
u Have ive Blood Poisoning ? ” 
I do not mean whether the deleterious ingredients existing in the 
atmosphere are subtle gaseous poisons, spores, or germs—that ques¬ 
tion we will waive; but do these deleterious ingredients which are 
existing in the atmosphere positively pass the barrier placed by our 
all-wise Creator in the membrane of the air-cells, and passing 
through it, really become commingled with the blood, poisoning 
that fluid, and entailing all the dire and often fatal consequence ? 
I am aware many of my professional brethren hold that they do. I 
maintain the contrary opinion, especially in chest influenza in the 
horse, and in pleuro-pneumonia in the cow. I grant you that the 
constitution of any horse is weakened and rendered more predis¬ 
posed to become attacked by any malignant disease, and if attacked 
is much more likely to succumb if he has been for some time pre¬ 
viously living in, or sleeping in, an atmosphere in which these 
deleterious ingredients exist, so much diluted with fresh air as 
not to be able to create active disease; the blood has not im¬ 
ported into it a destructive slow poison, but has become gradually 
deteriorated and suffers, inasmuch as it does not receive its ample 
