ON THE CONFORMATION OF HORSES. 
187 
cular, whilst it is in the air ; and that when the foot comes to the 
ground and sustains weight, it becomes 35°, the foot having de- 
clined 2°. The proper degree of declination is a point which 
ought to be particularly attended to; since a deviation from a 
healthy standard must entail a difficulty, at times an impossibility, 
in carrying on the proper action and spring of the hoof ; the laminae 
either being placed too much on the stress, or otherwise put out of 
use, when ruinous concussion is the result. The declination of 
the foot may become altered injuriously from a variety of causes; 
such as the animal being allowed to run on marshy grounds with- 
out shoes ; paring away the heels or toes unduly ; and, in heavy 
horses, thinning the sole, especially at the corn places, and low- 
ering the heels, thus allowing the foot to sink backwards and the 
sole to descend : too common a result in the English cart horse. 
To the same cause may be attributed the origin of the many horses 
we see with flat or sunken soles, totally unfitted for quick work. 
The relative depth of hoof to maintain the declination of 33° from 
the perpendicular should be, two at the toe to one at the heel ; 
and in healthy feet horn may be removed in these proportions, 
and our endeavour should be to bring back feet to this healthy 
standard, by lowering the heel or toe, or the adoption of thin or 
thick heeled shoes. Horses’ feet that have become very sunken 
cannot, of course, be brought back to the normal state. 
With regard to the Action of the Foot, in addition to the 
declination when placed on any yielding surface, f am of opinion 
that the points of the heels, when the frog is compressed, yield 
very slightly outwards, also that the remaining force is got rid of 
by the bulging out of the elastic matter round the coronet and at the 
bulbs of the heels, and that the sole of the horse’s foot, in a natural 
state, does not descend, except in the degree appertaining to it in 
the declination of the foot. When pursuing my studies on the 
foot of the horse, I have frequently been obliged to take plaster 
casts of feet, shewing the state both in rest and action ; and, I can 
safely affirm, that in no instance could I be induced to believe there 
was the slightest lateral expansion of the quarters of the horse's 
foot in the manner usually ascribed to it. I have very frequently 
measured, in the most careful manner, the dimensions of an unshod 
foot in the air, and also the impression of that foot taken upon 
clay, when a man had been seated on the horse’s back, and could 
not detect the slightest difference in the circumference of the lower 
edge of the hoof more than I have before stated. But in taking 
my plaster casts of the foot when in the air, and while supporting 
weight when on the ground, one important fact was always 
strikingly evident, viz. a declination of the hoof equal to 2 J . It 
would take up too much space were I to describe the varied expe- 
