62 
THE NAVICULAR DISEASE, OR CHRONIC 
of all joints is motion, Nature certainly intended it to have coi 
siderable action, although its sphere of motion appears vev 
limited. 
With regard to its short ligaments, it must be remember 
that it is never required to descend, except in connexion with tl 
small pastern and coffin bones; and, therefore, even viewed as 
process of the coffin bone, the shortness of the ligaments is 
favour of its descent. 
As to the binding appearance of the expanded part of tl 
flexor tendon, this does not, in reality, impede its descent, becaus 
at the instant the navicular bone descends under the weigli 
received from the small pastern, the fibres of the flexor perforar 
muscle are relaxed, and consequently the muscle and tendon a 
elongated. 
I wish it particularly to be understood, that I ascribe this grei 
freedom of action in the navicular bone only to very sound anj 
good actioned horses, and, to use a horseman’s phraseology, tl 
choice-gifted hackney, which is said to put his heel down firs 
Riding men know, what the driving men are not aware of,- 
that it is this sort only which is fit to ride. 
It will be recollected that I set out by expressing an opinion 
that the custom of confining horses by the head in the stable fd 
days and nights together, was productive of the chronic foe 
lameness. Although, as far as I am aware, writers on the foci 
have omitted to remark on this deviation from the natural habit 
of the animal, yet I am inclined to attach great importance t 
it, and fearlessly assert that it is one of the chief primary causes 
If I were asked what I thought mainly preserved the horse’j 
hoof, in a state of nature, from contraction, even to old age, : 
should say, the perpetual ?notion to which it was subjected by til 
natural habits of the animal in grazing; by which is preservei) 
a constant alternate descent and ascent of the heels of the coffii 
bone with the navicular bone. 
I shall now attempt to show in what manner so many con 
tracted feet in daily work escape lameness; but I am referring tl 
such feet only as are contracted, and have been known always t 
be free from lameness, and they continue to escape until the gene 
ral contraction becomes accompanied with the partial contraction 
before described, which, by compression immediately on the navi, 
cular joint, obstructs the function of that important and comple:, 
part of the foot; and this partial contraction is often preventet 
from following the general contraction by a combination of cm* 
cumstances frequently the result of chance, and the contraction o 
the hoof is rendered harmless. But the absence of the evil i 
more commonly to be attributed to diligent attention to the foot 
