424 



Pumice FOot. 



By whom or on what occasion the condition of foot T am about 

 to enter on the description of was first called pumice, I have not 

 been able satisfactorily to make out. Looking at the meaning 

 attached to the word in our dictionaries — which is spume oy froth 

 — and applying this in the sense apparently the most natural to 

 the case before us, it would seem as though pumice were intended 

 to designate the matters wliich had to appearance been ejected or 

 spued forth out of the horny case, such matters being sometimes 

 covered with spume or froth, and, from that circumstance, like 

 pumice-stone, having a porous aspect. Therefore, ?i pumice foot — 

 or, as Blaine has it, a pumiced foot — denotes, in the strict sense 

 of the word, no less than actual protrusion of the toe of the coffin- 

 bone, with its covering of sensitive sole, through the horny sole ; 

 though it is used also to signify that bulge and convexity of the 

 latter which is preliminary to its rupture, and the consequent pro- 

 trusion of the soft parts. 



The Pathology of Pumice Sole amounts to this : — In con- 

 sequence of inflammation in them, be that inflammation acute or 

 sub-acute, the sensitive laminae, from causes which have already 

 been detailed*, become detached from their union with the horny 

 laminae ; and the coffin-bone, losing its ties of suspension, is pressed 

 down by the weight upon the horny sole, which, unable to bear the 

 burden thus unnaturally transmitted to it, bulges, and either imme- 

 diately or some short time afterwards bursts, and lets the toe of the 

 coffin-bone, with its covering of sensitive sole, through its breach. 

 This, and this state of foot alone, it is, either actually present or 

 impending, which properly constitutes pumice foot. Flat feet, 

 nay, even convex and fleshy soles, do not of. themselves amount 

 to pumice ; but, on the contrary, may exist independently of it. 

 They may be, and are, dependent upon altered states of the hoof 

 alone; whereas pumice foot consists in disorganization of the 

 interior economy of the foot; — in altered structure and relative 

 situation of the parts within the hoof, and in partial escape of 

 them out of the hoof. 



* At pages 406-7, under " Pathology of Laminitis ;" and 420-1. 



