10 
WINDGALL AND BOG-SPAVIN. 
To the Editor of “ The Veterinarian .” 
My dear Sir,—As your paper in the last Number of The VE¬ 
TERINARIAN “ On Windgall” has drawn some remarks from one 
whose opinions on pathological disease I hold in high estimation, 
in which feeling, I am sure, you will join when I mention the 
name of the writer, Mr. Pritchard, of Wolverhampton, and as I 
have permission to make use of them, I do not think that I can do 
better than forward them to you. Perhaps at some future time 
Mr. Pritchard may favour us with a more lengthened statement 
on a disease but too frequently involved in obscurity. 
I am, your’s truly, 
W. Per civ all, Esq. ARTHUR CHERRY. 
“ In the last VETERINARIAN, Mr. Percivall says, windgalls, and 
bog-spavin, and thorough-pins, are the same in cause and effect; 
but my experience tells me differently. Windgalls are, as he 
truly observes, distended bursae by synovia, the product of work; 
and this is the true pathology of them, appear where they may, 
whether in the fetlocks, the hocks, or elsewhere. And abstinence 
from work, if of a sufficient time, particularly in a cool loose box, 
will remove them, if not entirely, to a very great degree. The 
undue volume of synovia becomes absorbed, and the sac reduced : 
and all this takes place without veterinary aid. But not so with 
bog-spavin and thorough-pin. This is a disease within the capsu¬ 
lar ligament, always the result of a sprain, and, unlike windgalls, 
the development of which is always progressively slow, appears 
rapidly after the accident. Bog-spavin does not disappear with 
rest; the disease proceeds: exercise promotes the absorption of 
windgall, but not of bog-spavin. The bursal tumour in the site of 
bog-spavin must not be mistaken for the latter; it is a very differ¬ 
ent thing. Some few years past I called the attention of Mr. 
Morton, in a conversation I had with him, to a chemical change in 
the constituents of the synovia in bog-spavin and thorough-pin ; in 
which that fluid first becomes highly charged with cartilage, then 
follows calcareous matter, and the whole tumour of the hock is 
converted into an ossific substance, of which T have a very large 
and excellent specimen. The first change in the synovia is in the 
increase of its albumen; then cartilage appears, most commonly in 
the form of cotton threads, from one to two inches in length, per¬ 
fectly white, resembling a fine needle-like worm, floating in the 
