194 
ON THE EPIDEMIC CATARRH. 
tlieirritable and debilitatino- state under which tlie system labours 
at these seasons of the year, whether spring, autumn, or winter, 
produced by moulting ; a process which deranges the whole con¬ 
stitution, and especially when, in autumn, a longer coat must 
be produced, it must call forth greater and increased powers 
from the constitution to produce that increase in the length of 
hair. Then, when the time of changing or moulting begins, and 
while the process is going on, the capillary and absorbent ves¬ 
sels must be in a state of increased action, for the purpose of 
supplying that demand, and to form that new growth of hair; 
while, by long or severe exercise, the lacteals having sucked up 
all the chyle, and the stomach not having a fresh supply of food 
to keep up a sufficient quantity of chyle to supply the lacteals, 
they then begin to take up (together with the other absorbents 
and inhalents, both external and internal) the air, with all the 
poisonous principles it may contain (and I think we can per¬ 
ceive it to have, comparatively, similar effects on plants); and 
this at a time when there is great irritation, and some degree 
of fever present in the system : the animal being weak, and 
sweating with little exercise, low and chilly, and thirsty, with 
impaired appetite. This predisposition in the horse at these 
seasons to febrile affection, and his being exposed to the cold 
damp air from the east or north-east, may well be imagined to 
produce catarrhal fevers, and diseases of the mucous membranes 
and respiratory organs, of the worst kind. 
Under these impressions, I ordered the men who had the care 
of the healthy horses to supply them often in the stable, or on 
the road, with a little hay or other provender, and not to lei 
them drink much cold water at a time, and not at all when they 
were in a state of perspiration; and 1 have every reason to be¬ 
lieve this advice had a good effect in preventing the disease; for 
I have not found one affected after this method was strictly fol¬ 
lowed, though they have, in many instances, stood next to a 
diseased horse. On the contrary, I have observed, that where such 
or a like plan has not been acted upon, very few, if any, escaped. 
Such, indeed, has been the prevalency and destructiveness of 
the complaint in this district, that very few establishments have 
been able to continue their works; and this without regard to 
close, small, large, crowded, ventilated or not ventilated, stables, 
or situations; but, perhaps, the low damp stables, near large ' 
waters, felt it most. It has been the same in the country as in 
the towns, pervading the whole country round for many miles, 
and in a very aggravated form, such as I have seldom met with ; 
and also affecting cows (chiefly those that gave milk) in a simi¬ 
lar manner. T observed, that if nitre or other strong diuretics 
