385 
ON THE EXTERNAL CAUSES OF 
DISEASE. 
flat, fluted paving stones, or brick, laid nearly level with a grat¬ 
ing or drain in each stall to keep it dry, which must have an 
outlet from the stable that will readily and easily carry oft the 
urine. The stalls should be large and roomy; and, if it is pos¬ 
sible, the horse should be allowed to stand loose. Loose boxes 
are particularly desirable for the carriage horses and hacks of 
private families, which have little work or exercise, and stand 
much in the stable. The benefits which hunters derive from 
standing in loose boxes need not be mentioned here. 
It is not our intention to enter farther into the minutiae of 
stable management; we shall therefore conclude this part of the 
subject by recommending that cleanliness should prevail in every 
department. Cleanliness is as necessary as pure air to the 
health of domesticated animals; indeed, we cannot well have 
one without the other; for he who has a clean and well venti¬ 
lated stable, will have a healthy stud, and the converse of this 
will never fail to engender disease. To obtain a full supply of 
pure air, two sets of apertures are necessary; one set in the up¬ 
per part of the stable for the escape of the heated and impure 
air, and another set close to the floor, to admit the pure air. These 
latter openings should be so situated that the air, on entering, is 
not directed in a current; but diffused generally throughout the 
stable. The same rule should be observed in the structure of 
the upper vent holes ; and seeing that the expired air always 
ascends in a direction perpendicular to the horizon, these aper¬ 
tures should be vertically placed. But when this situation can¬ 
not be obtained, we should endeavour to have them placed as 
near to the ceiling and as'far from the nostrils of the animal as 
possible. The apertures should be made in an oblique direction, 
which will give a free vent to the current of heated air, and at 
the same time protect the stable from wet and wind. 
But, owing to the peculiar construction and situation of some 
stables, it is almost impossible to have these openings above and 
below. Under such circumstances, in order to expel the heated 
and contaminated air, small tubes opening into the stable, either 
in or near the ceiling, should be carried to the top of the building, 
or be made to communicate with the external air by small per¬ 
forations through the wall. And in order to admit the fresh air 
into the stable (when circumstances prevent the apertures being 
made near the pavement), other openings should be made in the 
ceilings, having communications with small pipes that should 
lead from thence, either to the outside of the wall of the stable, 
or to any other part of the building that might be judged more 
convenient, where they should be bent, and conducted down¬ 
wards, till they reach the ground, where they should be left 
