THRUSH. 365 
tinued to exist. So, also, is it true that men have been scavengers, and 
have followed that calling on account of what they esteemed its extraor- 
dinary healthfulness. Neither case establishes aught. The animal is 
by nature formed for large draughts of pure air. All other sustenance 
is as nothing, if the primary necessity of life be withheld. Tainted 
atmosphere is the source of more than half the evils horse-flesh is ex- 
posed to. Glanders, farcy, inflammation of the air-passages, indigestion, 
bowel complaints,—in fact, all diseases save those of a local character 
may spring from such a parent. Let every horse-keeper, therefore, if 
from no higher motive, at all events to conserve his property and to 
promote his pecuniary interest, be especially careful about the purity of 
his stables. 
When thrush occurs in the fore feet, it is generally significant of 
navicular disease, and is most frequent in horses which step short or go 
groggily. The hoof feels hot and hard; a slight moisture bedews the 
central parting of the very much diminished frog. No odor may be smelt 
when the foot is taken up; but by inserting a piece of tow into the cleft 
of the frog, the presence of the characteristic symptom will be made 
unpleasantly apparent. 
In this case, it is best to remove the ragged thrush and unsound horn, 
doing so, if required, even to the exposure of the sensitive frog. After- 
ward, simply wash the part with a little of the chloride of zine and 
water, previously recommended. Repeat the cleansing every morning; 
the intention being, not to remove the thrush, as the horse mostly goes 
lame the instant that is stopped, but merely to correct the pungency of 
the morbid discharge, and thus prevent it in some measure from decay- 
ing the horn. 
Clay, cow-dung, and other favorite filths, employed for stopping the 
horse’s feet, if long continued, will produce thrush. 
The worst specimen of the affection the author has encountered, was 
in a horse which had been turned into a moist straw-yard and neglected. 
The thrush generally witnessed in the hind feet may be present in all 
four; but the writer knows of no instance in which the thrush peculiar 
to the fore feet was also observed in the posterior limbs. 
Thrush does not generally provoke lameness. In its more aggravated 
forms, however, it interferes with the pace; and the horse having only 
incipient thrush is liable to drop suddenly, if the foot be accidentally 
placed upon a rolling stone. Now, knowing our roads are made of 
stones, and that the bottom of the horse’s foot is, in the ordinary man- 
ner of shoeing, entirely unprotected, it is curious to state that this dis- 
ease is commonly not esteemed unsoundness. Any thrush, when present, 
may lead to acute lameness; then the lameness would be unsoundness; 
