MEMOIRS OF A VETERINARY SURGEON. 
17 
all these cases of excitement of the lungs and air-passages, 
the air expelled is charged with more carbonic acid, more 
animal matter, more animal heat, and more aqueous vapour 
than it is when these organs are in their natural and healthy 
condition. The particles of air, too, are driven with greater 
rapidity and force into the surrounding atmosphere, disturb¬ 
ing its electrical state; and this more especially when the 
animal is circumstanced as above stated ; that is, breathing 
in a limited space. We also know that moisture affects the 
electrical state of the air, and there are likewise other ele¬ 
mentary conditions disarranged, and combinations formed; 
and if these influences are in operation for several consecu¬ 
tive hours, 1 am fully persuaded that a particular state of 
the air is induced in a high degree deleterious to health, 
the state being one which fosters and perpetuates diseased 
action. This is the sure and certain result. The late 
Professor Coleman called it “ animal poison . 19 Suffocation 
results in the same manner from vitiated air as from an in¬ 
terception of it; and science has shown that carbonic acid is 
not in itself a poison, but kills by producing suffocation. 
We do not, however, know the whole truth yet; I mean 
the exact alteration produced in the air consequent upon 
these changed conditions. Nor, in our present state of 
knowledge, do our highest attainments in science, or our 
most delicate instruments, take cognizance of it; neither do 
I believe the truth has in all its entirety ever yet flashed 
across the brightest intellect—it requires a more elaborate 
scientific investigation. But because we cannot clearly and 
fully understand and explain these obscure phenomena, let 
us not ignore them, and affect to disbelieve that a vitiating 
influence is being exerted. Depend upon it, it is no chimeri¬ 
cal idea. Every intelligent and observant practitioner has, I 
doubt not, over and over again convinced himself of its 
baneful effects, and, being assured of its pernicious nature, he 
at once removes his patient, without a moment’s loss of time, 
to a more congenial atmosphere. 
TREATMENT OF THESE CASES. 
It is, nevertheless, a well-known fact that disease often 
attacks horses occupying stables where every attention is paid 
to proper ventilation and cleanliness, and animals, too, with 
healthy constitutions; but their diseases are, comparatively 
speaking, few in number, and far less inveterate than in those 
horses that are otherwise circumstanced. In my practice, in 
horses having these advantages, the cases of fatality do not 
average more than one per cent. Their attacks are generally 
xxxiii. 3 
