SUB-ACUTE LAMINITIS. 421 



period of life, generally at sight, distinguishable from it. This 

 established deformity of foot it is that constitutes what is called 

 pumice sole. 



The Causes of Sub-acute Laminitis are not always evident. 

 There can be no doubt but that certain descriptions of feet, such as 

 large and flat and weak feet, are from their conformation predisposed 

 to the disease, on the same principle as they are to acute laminitis. 

 As one sort of foot is predisposed to navicularthritic disease, so is 

 another to disease of the laminae; and therefore it is that the excitant 

 — which, in both instances is, in one comprehensive word, work — 

 is likely to produce laminitis in one case, navicularthritis in another, 

 according as the foot to which it is applied be of this or that 

 character. But acute laminitis is very often referrible to a distinct 

 act of over-work or excessive exertion, which is rarely the case 

 in the sub-acute affection. We certainly find the disease some- 

 times creeping on the horse while he is at work ; but then, again, 

 we find it come on him during the time that he is idle or even 

 absolutely at rest. Within these few years past I have had in my 

 practice two remarkable instances of this. 



An old horse, three-parts-bred, who had done a great deal of 

 work in the royal stables, and who, at the time he was growing 

 stale upon his legs and feet, was presented by the Queen to Col. C, 

 after having in the Colonel's service, as an occasional charger, 

 done little else but taking daily walking exercise for the space of 

 about three years, became attacked with sub-acute laminitis, first 

 in one fore foot, then in the fellow one. The disease was subdued, 

 but returned, and returned after this again ; and in this way, after 

 being from time to time combatted with and checked, ultimately 

 ended in pumice feet, through which the horse was rendered un- 

 serviceable, and in consequence was destroyed. Another case of 

 the kind occurred in Major B.'s charger. This horse, during the 

 time his master was on the continent, had been laid up, alias turned 

 loose in a box without shoes on his feet, to do nothing. During 

 this state of idleness he was attacked, in the same insidious manner 

 in which the Colonel's horse had been, with sub-acute laminitis; 

 for which, after being twice so far relieved and patched up as to be 

 enabled to attempt his work so far as walking for the space of a 



