258 ON THOROUGH-PIN, WLNDGAI.L, &c. 
infiltrations under the mucous membrane, in the secretory tex- 
tures , and in the cellular texture which surrounds them. I have 
also seen true false membranes, of greater or less consistence, in 
the interior of the articular capsules. These false membranes, 
which were sometimes adherent by a few points, and at other 
times free in the cavity, presented a great variety of consistence 
and of colour. I have sometimes traced in them much analogy 
with the fibrine that is obtained by agitating and washing 
blood ; but they bore the greatest resemblance to the organized 
bodies that are found in certain serous abscesses, the conse- 
quence of long-continued compression or friction on certain su- 
perficial regions of the body, as the hock or the elbow. Some- 
times these false membranes present themselves under the form 
of h ighly polished, white, and hard lenticular bodies, swimming 
in the synovial fluid. 
When the thorough-pins are of long standing, and very large, 
and their walls, forming an infinite number of cells of various 
forms, are become cartilaginous, and even bony, I have seen 
the membrane and the articular cartilage destroyed, and their 
bony substance worn away like so many furrows. It is very 
probable, that when the thorough-pin has attained the state of 
which 1 have just spoken, that the synovial membrane has been 
destroyed in many points, corresponding with the cavernous di- 
verticulum of which 1 have spoken, and that the internal mem- 
brane is a new formation. The destruction of the synovial mem- 
brane cannot possibly be doubted when two neighbouring 
articular cavities, naturally separated, unite into one. This last 
state, and the wearing away of the cartilages and even of the 
bones, is sometimes met with in old horses, when there was no 
reason to suspect the existence of any articular disease. 
The synovial fluid is also altered; usually it becomes more 
liquid, and of a deeper colour, and it is not so oily as in its na- 
tural state. 
1 care less about the theory of the development of thorough- 
pins and windgalls than of the means by which the formation of 
these diseased structures may be prevented, or successfully com- 
batted in every period of their growth. 
I do not pretend to have discovered any remedy of a marvel- 
lous nature, nor to accomplish more than my brethren are ena- 
bled to do, or have done ; perhaps my mode of treatment may 
not be essentially different from that which has been adopted or 
attempted by others. The same means are not applicable to the 
same lesions in every part. I could not treat thorough- pins of 
the hock and windgalls of the fetlock precisely in the same 
way. 
