LAMENESS, FROM VARIOUS CAUSzs. 331 
The authorities teach us, and my own experience has vonfirmed 
the fact, that iodide of potass is a valuable agent ix. the treatment 
of chronic rheumatism. It is most sure to act beneficially when 
the periosteum (fibrous covering of the bones) is affected. There 
is no doubt that chronic rheumatism often cripples the joints by 
producing disease of the bones in the region of their articulations. 
This makes a poor horse dead lame, and renders him almost useless. 
When the bones become ulcerated or carious there remains but little 
hope of cure. 
RING-BONE, 
Ring-bone is a form of disease the pathology of which is similar 
to that of spavin and splent, It is located just above the coronet 
or crown of the hoof. The enlargement is called exostosis (a mor- 
bid enlargement of bone), and when the iarge pastern becomes 
united to the smaller one, the case is called anchylosis (permanent 
rigidity of the joint). 
The term ring-bone is far behind the times as regards our pres- 
ent knowledge of nosology (the doctrine of the names of diseases) ; 
yet, to the unprofessional, it is suggestive, and, therefore, we are 
compelled to retain a rame which all can interpret. It signifies 
a complete or partial eminence around pastern bones. The ring 
is formed by incrustations, or osseous deposits in the pastern, or 
involving the joint, as the case may be; yet, in order to make out 
a pure case of ring-bone, that comes strictly within the meaning 
of the term as horsemen interpret it, there must exist a complete 
ridge of bone around the anterior part, extending from side to side, 
A pure case of ring-bone generally originates on the surface of the 
bone, on or beneath the periosteum. Commencing at the lower 
margin of pastern and upper part of the coronet bone, the disease 
spreads, involving both capsular ligament and joint. The remote 
cause of ring-bone lies in hereditary idiosyncrasies, transmitted 
through the sexual congress. The disease itself is sometimes di- 
rectly transmitted. I once bought an unweaned colt, and brought 
it up by hand. A short time after purchase, I observed enlarge- 
ments on the hind pasterns. He ultimately turned out to be a 
ring -boned animal, and had stiff jointa. I found out afterward 
that the mother had large ring-bones on both hind pasterns. The 
disease was, therefore, congenital. 
Mr, PERCIVALL, whose opinion on such watters is unquestion 
oD 
ee 
