500 REMARKS ON MR. CHERRY’S PAPER ON CORON1TIS. 
of by far greater importance than either of the other secreting 
parts of the foot, and in this disorder most certainly participating, 
to a very great extent, in the diseased action, yet I do not con- 
sider that we should be justified in regarding it as the seat of an 
affection which, in my opinion, is dependent upon a general dis- 
turbed action affecting the whole of the textures of the sensible 
foot dependent upon excited irritability. 
The sensible secreting surfaces of the foot have all of them been 
proved to be continuations of the true skin ; and it is in consequence 
of this that they are so frequently S3 r mpathetically diseased in 
fevers and other affections in which the skin is diseased, such as 
grease in the production of canker, & c. The law of sympathy being 
thus so well established between the skin and the secreting sur- 
faces of the foot, and those parts being so very similar in structure 
and function to each other, I consider that it would be impossible 
for any one of them to remain chronically diseased for any length 
of time without, in some measure, affecting the others; so that, 
that which was at first only the effect of disease in a neighbouring 
part, may soon become a cause, merely through the influence of 
sympathy. 
With reference to the statement made by Mr. C., that tar, See. 
does not become absorbed when applied to the hoof with a view 
to soften its texture and render it tougher and less friable, I must 
beg to disagree, in toto. He says, “ examine a foot that has been 
stopped with the common tar ointment, and it will only be found 
to have penetrated so far as there may be a portion of dead horn.” 
So far as the power of our visual faculties will enable us to detect 
its farther progress, I am free to admit that he is correct ; but our 
olfactories, I presume, are too often made aware of its presence in 
living horn to allow of its absorption being denied. 
Evaporation from the outer surface of the wall, unless in a very 
limited degree indeed, so little as not to be of the slightest im- 
portance, I am inclined altogether to disbelieve, unless it is im- 
mediately after the rasp has been applied, as in the operation of 
clenching the nails, for the crust has the power of throwing out a 
kind of epidermis, which effectually prevents evaporation ; but this 
epidermoid covering being removed in the operation above alluded 
to, together with some portion of the crust itself, the most external 
pores are consequently left open, and evaporation is the consequence : 
in a very short space of time, however, this defence is again pro- 
duced, and evaporation arrested. If we deny absorption ever taking 
place in healthy horn, how are we to account for the fact that two 
pieces of this material, both taken from a sound foot, the one im- 
mersed in tar and the other in grease or oil, and allowed to remain 
there for some time, do, when taken out, present remarkable altera- 
