386 
ON TIIE EXTERNAL CAUSES OE DISEASE. 
open to communicate with the external air. By this plan, the 
cool external air would be forced in at the lower openings of the 
tubes, and made to ascend into the stable, in proportion to the 
quantity that escaped towards the higher regions, by means of 
the ventilator. We are aware that this plan is a complicated 
one; but when, by means of the situation of the stable, it is 
impossible to have direct openings below, or above, we think it 
a desirable one # . It has in one respect an advantage over the 
former one with those persons who require an extra degree of 
heat in the stable, and yet wish to get rid of the foul air ; inas¬ 
much as the air which is admitted from without will be so dis¬ 
persed about the apartment, that it will supply the inmates 
with a sufficient quantity of fresh and vivifying air, without any 
of those inconveniences to which they might be subjected by 
the usual way of admitting it. 
By either of the plans which we have mentioned we shall ob¬ 
tain a sufficient degree of warmth necessary to the health and 
well-being of the animal, combined with a free circulation 
of pure atmospheric air. From what has been stated, it must 
appear that we are no advocates for keeping horses hot, but only 
in a certain degree of warmth, that is as requisite to their well¬ 
being as to ourselves. 
Throughout the great diversity of climates, from the burning 
sands of Africa to the frozen regions of the north, it is observed 
that all-provident nature, with a view to the preservation of 
animal life and health, has carefully accommodated the constitu- 
tionsof animals to the temperature to which th$y are destined to 
be exposed. The horse thrives best in temperate climes, for 
either in extreme hot or cold countries he degenerates. Cli¬ 
mate, in its most extensive sense comprehending atmosphere 
and soil, has had almost unbounded influence on the characters of 
animals. The activity, irritability, and sensibility, usually 
observed in horses possessing much “ blood, 7 ' are never found 
in those of the huge heavy draught kind. These qualities are 
the natural production of a warm climate, a gentle elevation of 
soil, and a serene and equal atmosphere. The same etifect is 
produced in man as among the inferior animals. 
Now let us briefly consider the external signs by which we 
are capable of ascertaining that men and horses are in that con¬ 
dition, which will enable them to do the greatest possible de¬ 
gree of work with the least possible degree of fatigue. It 
is not from the sleek countenance, nor from the plump ha¬ 
bit, as indicating distended vessels, that we are to form 
* Probably some of the readers of The Veterinarian will favour us 
with plans for the ventilation of stables under such circumstances. 
