530 
ON HOCK LAMENESS. 
could be said to have taken place in this joint unaccompanied by 
open joint or some external injury:” this is, certainly, rather 
contradictory. 
Mr. Dick goes on to say, “ there is, perhaps, nothing more 
common that to observe the effects of friction on the articulating 
surfaces of these bones; but then it is quite different from what 
Mr. Spooner points out.” It is, certainly, somewhat strange, 
if this friction is so very common , that it has never been pointed 
out by any of our veterinary writers or lecturers ; and it is equally 
singular that the first person who referred to this articulation as 
the seat of disease should have mistaken a healthy structure for 
a diseased one. 
Mr. Dick remarks, that the symptoms of this friction prior to 
death are also <s quite the reverse” of what Mr. Spooner points 
out. Now, as Mr. D. does not tell us the symptoms he has 
found which are so opposite to mine, we can only gather them by 
taking the “ reverse” of those I have pointed out. I have said 
that there is a lameness behind, which lameness generally di- 
minishes after exercise. Mr. Dick’s symptoms we are to under- 
stand are “ quite the reverse.” 
Mr. D. says, that if I reflect for a moment I shall see that the 
situation of the cavities I describe renders friction impossible. 
Now, let us suppose, for a moment, that all hocks possessed 
certain irregular cavities on the ridge of the tibia. What, then, 
are the most likely parts to suffer from friction ? Why, I should 
say the edges or borders of these cavities ; and thus, even if 
they existed in all hocks, the fact would not militate against my 
theory ; for abrasion may take place on the edges of these 
cavities, and the synovial membrane may be bruised, the carti- 
lage absorbed, and the same appearances presented as we find 
in the fore feet in cases of navicular lameness, and which we 
there call ulceration. 
But let us suppose the case of a healthy hock, in which these 
cavities do not exist. A bruise takes place at the part I have 
pointed out — the centre of the joint, the fulcrum of motion ; in- 
flammation ensues from this bruise, and lameness is produced : 
the horse, however, continues working, and the lameness in- 
creases ; the cartilage of the bone becomes absorbed, and, 
perhaps, the bone itself. The horse is now regularly treated, 
and rested for a long time, and he gets apparently well. What 
is the cause of this amendment? Why, the inflammation has 
subsided in the joint, and the injured part has, perhaps, been 
removed, by absorption, from contact and friction, which, in- 
deed, may be considered as one of Nature’s efforts in protecting 
parts from injury. The horse, however, is again put to hard 
