REVIEW. 
37 
outward direction in its growth downward. These several 
parts, viz. the laminm, the sole, the frog, the cartilages, and 
the horn at the coronet, as soon as the expanding force is 
removed, by virtue of their own inherent elasticity, recover 
their original dimensions and relations. 
Coleman’s work may be cited as authority in proof of the 
truth and genuineness of these statements. 
“ The horny sole, frog, and bars, have their respective func¬ 
tions, and their uses are highly important; but they do not per¬ 
form the function commonly ascribed to them, that of supporting 
the weight of the animal; indeed 9-10ths at least of the sensible 
and horny frog are placed behind the coffin-bone, and therefore 
cannot support any considerable part of the weight. The 
laminae, about 500 in number, at every step act as so many 
elastic springs,” &c.—“This elongation of the laminae is, in¬ 
deed, one great excellence of that wonderful piece of mecha¬ 
nism ; for, if the same extent of surface, and the same degree 
of strength of union, had been formed of bone, or any other 
inelastic substance, concussion or fracture would probably have 
followed. Without motion there can be no spring, and as both 
horny and sensible laminae are elastic in their structure,” See* 
“ whatever, therefore, may be the degree of motion in the 
coffin-bone, the horny sole opposite must alwsys descend in the 
same proportion,” &c.t 
“ That the use of the horny frog is to prevent the horse from 
slipping, by its convexity embracing the ground, and from the 
elasticity of the sensible and horny frogs, they act as a spring 
to the animal, and keep expanded the heels.”| 
“ In the natural state, when the horny frog meets the ground, 
the superior portion of the sensible frog ascends between the 
side cartilages, and the wedge-like form of that organ necessarily 
opens the heels of the side cartilages. The expansion of the 
side cartilages, at every ascent of the horny and sensible frogs, 
not only gives a powerful spring to the animal, and enables the 
frogs to complete their function, but the direction of the growth 
of the crust at the quarters and heels is absolutely governed 
by the motion of the side cartilages.”^ 
Now, unless it can be denied that these passages comprehend 
the principle of the elastic property of the hoof as an integral 
structure, seeing that. Coleman’s work was published in 1802 and 
* Observations on the Structure, Economy, and Diseases of the Foot of the 
Horse. By Edward Coleman, Professor at the Veterinary College, 1802. 
Vol. ii, pp. 82, 84. 
f Op. Cit. vol. ii, p. 65. 
X Op. Cit. vol i, p. 106. 
§ Op. Cit. vol. ii, p. 68. 
