ON HOCK LAMENESS. 
532 
cartilage on the surface of the bone, likewise, is not worn down by 
friction, like the axletree of a wheel, as Mr. Dick's observations 
would imply ; but, in consequence of continued pressure, an 
absorption takes place. The loss of substance occurs from 
the action of the absorbents, and not from being ground down 
like corn in a mill. 
With regard to bog-spavins, every one knows — at least every 
veterinary surgeon, if he knows any thing at all — that not one in 
twenty occasions lameness. I am, therefore, hardly prepared to 
acknowledge, that every ease is attended with friction, or rather 
the effects of friction, within the cavity of the joint ; and if, as Mr. 
Dick asserts, bog-spavins are commonly the effect of injury done 
to the ligaments outside of the joint, there is still less reason for 
supposing that friction must necessarily and invariably be pro- 
duced within the cavity. 
I would not by any means assert that there are no instances 
of small excavations occurring in the centre of the hock joint in 
a state of health ; but I would simply observe, that, in spite of 
their invariable and essential existence, for which Mr. D. con- 
tends, I have at present some healthy hocks before me which 
discover no such appearances, either externally or internally. 
As my paper has extended much beyond its intended limits, 
I must now leave the subject to the consideration and observation 
of the profession ; but in doing so must observe, that my opinion 
remains entirely unaltered by Mr. Dick's animadversions. I am 
still convinced that the rough and irregular abrasions which I have 
pointed out were produced by disease, and were the causes of 
lameness in the cases I have recorded. 
ON HOCK LAMENESS. 
By Mr. Pritchard, of Wolverhampton . 
Always awake to any thing new connected with the veterinary 
art, I was forcibly attracted, in the month of December 1830, 
by Mr. W. C. Spooner's paper on Hock Lameness, wherein he 
cited some four cases of disease, situated between the tibia and 
astragalus ; and although I could not subscribe to his pathologi- 
cal views of the subject, still I thanked him for his information, 
and ranked his cases as new in veterinary nosology. Mr. Spooner 
appeared at the time desirous that the profession should make 
some observations on the subject of his paper; however, all con- 
tinued silent up to 1837, when Mr. Spooner's patience, it would 
seem, became exhausted, and he again brings the subject before 
