180 
THE HORSE.-NO. O. 
preparing* the medals—publishing a report and in 
additional premiums. 
All editors of periodicals friendly to agricultural 
pursuits throughout the United States are respect¬ 
fully requested to publish the above. 
Perkins & Brown. 
Springfield, Mass., April, 1847. 
THE HORSE.—No 5. 
The Arm. —The arm consists of two bones, and 
extends from the elbow down to the knee. The 
longest of the two is called the bone of the arm, or 
spoke bone; is nearly straight; bears at its upper 
end the lower shoulder bone, and rests at its lower 
end on the bones of the knee. It is in front. The 
hinder and shorter bone is called the elbow bone. 
It has a long and powerful projection behind, called 
the elbow, which extends from the lower bone of 
the shoulder down to the middle of the front bone, 
and there ends. These two bones are united by 
cartilage and ligament, which are changed gradually 
in horses of five to eight years of age, to bone, and 
then the arm consists of only one bone. The short 
bone acts as a brace. The weight of the body and 
the shock of motion falling on the arm, are divided 
between the two bones. The cartilage and liga¬ 
ment in the young horse between them, assist to 
resist the combined effect of weight and jar ; in the 
old horse, the united bones do the same. These are 
made one by the in¬ 
flammation and irrita¬ 
tion arising to the car- 
lilages and ligaments, 
from the great work im¬ 
posed on them. These 
two bones are surround¬ 
ed by very tendinous 
muscles of great volume 
and force, which are 
immense where they 
attach to the elbow, 
and the cartilages and 
ligaments correspond 
in power. The arm of 
the horse should be 
large, as his strength 
in front lies mainly 
here. It should be so 
formed as to allow 
the attachment of large 
muscles, and of their 
action to the best ad¬ 
vantage. A large and 
properly formed elbow 
is very necessary for 
this purpose. The 
Muscles of the Inside of longer the elbow, the 
the Arm—Fig. 36. better will the muscles 
act, as they will exert their power in lines nearer 
to the perpendicular than with a short elbow. 
The Muscles of the Arm. —We have already de¬ 
scribed the muscles, r, r, s (fig. 25). These were 
common to both arm and shoulder, as indeed are all 
the muscles of the arm in some degree, but those 
were peculiarly so. 
The chief muscle of the arm is the extensor or 
extending muscle employed to raise and project in 
front the bones of the leg below the knee, viz : the 
cannon or shank, and splent bones. It is seen at x, 
fig. 25. It is attached at its upper end, to the head 
of the lower bone of the sliouldei* at the point, and 
to the ligament that covers the joint at the point of 
the shoulder; the upper part of this muscle is 
mainly flesh with small tendons; pt its middle part, 
it becomes tendon almost wholly, and a little fur¬ 
ther down entirely so, and proceeds as a tendon, 
round at first, but flat at the knee, where it attaches 
itself. It is continued on and attached to the upper 
end of the shank bone. 
w, fig. 25, shows the extensor of the foot or mus¬ 
cle extending the foot. It is the second in impor¬ 
tance in the arm. It starts from the shoulder joint, 
being attached to the fore part of the head of the 
lower bone of the arm. It is flesh where it starts, 
runs downward, and before it reaches the knee be¬ 
comes tendinous wholly, and proceeds on to the 
fetlock and pastern, where it attaches itself by liga¬ 
ment covering and adhering to the pastern joint It 
not only raises and extends the foot,but also the knee. 
u and 2 , fig. 25, are tendons of two more extend¬ 
ing muscles. These serve the same purpose as the 
other extensors. 2 runs obliquely across the 
muscle x, confining it in its place. 
The muscles employed in bending the leg back¬ 
wards, are numerous and powerful. One is seen at 
b, on the leg, in fig. 25, and at b in fig. 36, and is 
called the middle bending, or flexor muscle of the 
shank and splent bones. The external flexor is 
seen at v, fig. 25. The internal flexor is seen 
at e, fig. 36. There are two muscles among others 
whose object is to raise the foot. They are 
called the perforating extensor and the perforated 
extensor of the foot; the perforating, so called, be¬ 
cause it runs through the other, and due. perforated 
because it is run through by the perforating. They 
lie at the back of the arm. The perforated one, 
joined to the perforating, forms a large fleshy mass. 
As it goes downward, it becomes tendinous, and at 
the knee is fastened down by ligaments; below the 
knee it widens, and partly encloses the perforating 
flexor, and they run down together to the fetlock, 
where the tendon of perforated muscle forms a ring 
around the perforating tendon ; below the fetlock, 
the perforated tendon divides and attaches itself on 
to the pastern bones. Both the perforating and per¬ 
forated are enclosed in a sheath of dense cellular 
substance which is attached by fibres, and they are 
supported and bound round by many ligaments. 
Th e perforating flexor muscle has a common 
origin with the perforated. It is muscular further 
down the.arm, and lies before the perforated. It is 
confined strongly at the knee by ligaments. At the 
knee it is round, and is partly enclosed in the perfo¬ 
rated ; it proceeds to the fetlock, where it is en¬ 
closed wholly by it. When the perforated tendon 
divides and goes to the pastern bones, the perforat¬ 
ing comes out of its enclosure, and goes into the 
back part of the foot. 
One of the most powerful of the muscles which 
bend the arm is the flexor of the arm. It arises 
from the lower end of the ridge of the shoulder 
blade in the form of a large round tendon, and runs 
in a groove between the two elevations in the up¬ 
per part of the front of the lower bone of the 
shoulder. The groove is lined with smooth carti¬ 
lage, and an oily fluid fills it, for the tendon to 
