88 DADD'S VETERINARY MEDICINE AND S JRGERY. 
they keep but few animals, disease and death, except in cases of 
accident or old age, are quite rare, but so soon as tuey crowded 
the same, sickness and death were the consequerves, In view of 
supporting this theory, we may be permitted 4c remark that ship 
and jail fevers may be manufactured ad lWWiivm, at any time when 
a large number of persons are congregate] together in a given 
space, no provision having been made fur the admission of pure 
air. The unfortunate prisoners in tee Black Hole of Calcutta 
are an example, and the mortality sceurring on board ovr emi- 
grant ships furnishes another illus! cation. 
A number of horses were once sbipped from England ‘« Spain, 
and on the passage, a violent gale arising, it became recessary tc 
batten down the hatchway. The consequence was that most of 
them ultimately died of either glanders or farey. We conten, 
therefore, that the active or morbid germ of disease enters the 
living citadel through the pulmonary tissue in an insidious mar- 
ner, and, therefore, much oftener than the generality of men 
would be likely to realize. Therefore, it is a matter of vital im- 
portance that attention be paid to the ventilation of our stables. 
If proper sanitary regulations were established, and fully carried 
vut in all our stables, glanders and other infectious diseases would 
be exceedingly rare. They are so among horses free from the 
eontrol of man, whose stalls are broad as from ocean to ocear, 
their height ranging from earth to regions above, the space per - 
vaded by a pure atmosphere concocted by the Great Chemist, pure 
as the pearly drops and refreshing as the morning zephyr. Is 
such locations death has no terrors nor disease any victims. 
Brier EXPosiTioN OF THE FUNCTION OF THE LuNGs. 
The principal function of the lungs is to arterialize or decar 
bonize the blood; that is, purify it. This arterialization of the 
blood, which goes the rounds of the circulation, is more essential 
to life than either food or water ; for men and animals can exist 
for several days, perhaps for two weeks, without food, yet the 
same can not live over a few seconds unless supplied with a suffi- 
ciencv of atmosnheric air, Hence. in a popular sense, pure air is 
the “ treath of life.” 
The functional acts of respiration are necessarily divided inte 
two parte: and in cattle the number of respirations are about 
