THOUGHTS ON BROKEN WIND. 
65 
wind; though this, I expect, was a spasmodic nervous attack 
caused by the animal being nearly in a state of asphyxia. But 
these cases recovered: in fact, I only consider them to have 
been affected with symptoms natural to horses nearly suffocated. 
A long continued inhalation of noxious gases might, perhaps, 
cause chronic bronchitis, and so pave the way to broken wind. 
Rather a curious point is connected with this; and as any thing, 
however slight, is worth notice, I shall mention it. There is a 
peculiar asthma in man called the hay asthma , and people so 
affected cannot bear the smell of new hay, since it immediately 
produces distressing attacks of dyspnoea. Our late sovereign, 
William IV, was an instance of this, and he had always, in con¬ 
sequence, to reside at Brighton during the hay season. 
Turning old horses that have been long stabled to grass or 
straw-yard is a very fruitful source of broken wind ; and it is 
difficult to say whether this arises from the comparatively innu- 
tritious quality of the grass, which may produce some disordered 
state of stomach and sympathetically affect the lungs, or 
whether (as the mucous membranes are only a continuation of 
the skin) the sudden exposure to cold simply produces an affec¬ 
tion of the air-passages, ending in broken wind. It is most 
probable, that animals which on return from grass have thus 
been said to have gone broken-winded, had been affected with 
chronic cough for some time previous to their being turned out. 
Enlargement of the air-cells or dilatation of the bronchial 
tubes may produce broken wind, on the same principle as em¬ 
physema ; because the aperture for the expulsion of air retains 
its original size, or is perhaps smaller, and the parts which re¬ 
ceive and contain the air are increased in size: hence the diffi¬ 
culty in expiration. But when the bronchial tubes or air-cells 
are merely dilated, it is only the first step towards broken wind, 
the difficulty of expiration being at such a time not so great, 
perhaps, as to make it perceptible unless closely looked for. 
How far may asthma in man and broken wind in horses be 
considered analogous diseases 1 There are some forms of 
asthma, especially such as seem to arise from similar causes to 
broken wind, which do bear a close resemblance. The asthma 
which commences in chronic bronchitis, and congestive asthma, 
are of this kind; but still, in some respects they differ from 
broken wind. We must not forget, that in man attacks of 
asthma are brought on, or increased, by emotions of the mind 
and affections of the senses; and that it is in many cases with 
him purely a nervous disease, no trace of morbid lesion being 
found in the chest alter death. And again; that there is no 
case of asthma in man that is not greatly complicated with 
nervous excitement. Now, in the broken-winded horse, I con- 
VOL. XXV. K 
