G10 ON BREEDING. 
the .size of the lung's are the form and size of the chest, the 
form of which should approach to the figure of a cone, having 
its apex situated between the shoulders and its base towards 
the loins. The capacity of the chest depends on its form more 
than on the extent of its circumference; for where the girth is 
equal in two animals, one may have much larger lungs than 
the other. A circle contains more than an ellipsis of equal 
circumference; and in proportion as the ellipsis deviates from 
the circle, it contains less. A deep chest, therefore, is not 
capacious, unless it is proportionately broad. The most expe¬ 
ditious way to obtain horses with large lungs is to cross well- 
formed females from a variety of a large size, with well-formed 
males of a variety that is rather smaller. By such a method of 
crossing, the lungs and heart become proportionately larger, in 
consequence of a peculiarity in the circulation of the foetus, 
which causes a larger proportion of the blood, under such 
circumstances, to be distributed to the lungs than to other 
parts of the body: and as the shape and size of the chest 
depend upon that of the lungs, hence arises the remarkable 
large chest which is produced by crossing with females that are 
larger than the males*. ’ 
This practice may, be a profitable one to breeders of cattle, 
but certainly ought not to be carried too far by breeders of 
horses, except for those horses who are employed to move heavy 
loads; since the bulk of the body might be so disproportioned 
to the size of the limbs as to prevent the animal moving with 
sufficient facility: for in proportion as you increase the size of 
the chest, you diminish the animal’s speed. An example of this 
is seen in the bull-dog and greyhound: the former is distin¬ 
guished for his broad chest, his strength, and disposition to fatten 
on small quantities of nutriment, but wants that agility and 
swiftness of foot so characteristic of the breed of the latter. 
A very wide chest is usually accompanied with what are 
commonly called “ thick or heavy shoulders:” the cause is 
owing to the shoulders being so far apart as to give them 
an overloaded and muscular appearance. The shoulder-blades 
ought to be muscular, yet not overloaded with flesh: if too 
lean, they want strength; if too heavy, they impede progression. 
They should rise high up to the withers, gently inclined back¬ 
wards, and so beautifully adjusted, that in descending a hill 
the point never ruffles the skin. 
There are few rules that can be laid down on the general con¬ 
formation of the horse more to be relied on than this, that a short 
and upright shoulder, particularly if the whole limb is inclined 
* Mr. Cline’s Observations on Domestic Animals. 
