192 
MR. YOUATT S VETERINARY LECTURES. 
\ 1 
of pain ; and on which, through every gradation of animated na¬ 
ture, comprising more numerous species and lower grades of be¬ 
ing than some have imagined, depend, likewise, all the powers 
of mind and the capability of moral feeling. Next, the sources 
of organic life ; whether that important nerve, proceeding from 
the ganglion at the base of the atlas [a dissection was here ex¬ 
hibited], or those innumerable radiations of nervous influence 
from the semilunar ganglion, and proceeding to every viscus 
and entwining round every vessel, and by deriving power from 
which the heart beats, and the lungs heave, and the stomach 
digests, and the capillaries secrete,—unconnected with sensation, 
unless by anastomosis, w ith the spino-cerebral nerves—and inde¬ 
pendent of the will: or whether that newly-discovered system of 
nerves—newly-discovered as to function—partly involuntary and 
partly under the influence of the will—acting when we are un¬ 
conscious of their action, and deriving their sensation from union 
with the spino-cerebral—proceeding from the lateral portion of* 
the medulla oblongata [the brain and spinal cord were here 
shewn], and occupying the lateral column of the spinal cord—a 
kind of neutral ground—communicating to or deriving assistance 
from the motor and the sensitive columns on either side—given first 
to the organs concerned in the function of respiration, and descend¬ 
ing to every viscus connected with organic life:—these, together, 
constitute a most interesting although an obscure system; and 
we must obtain some comprehensive knowledge of them before 
we are qualified to enter into the full consideration, or to under¬ 
stand the functions of any portion of the frame. 
We commence with the Brain. It is enclosed in a bony cavity 
situated in the postero-superior part of the head; of an ovoid 
form; rounded above, flattened below [the cranial cavity was 
shewn], broader anteriorly than posteriorly; longer than wide 
in the proportion of seven to four, and its height less than its 
width. 
It is composed of several bones,—the two frontals forming 
the anterior portion of the roof, and the antero lateral portions; 
the two parietals occupying the middle of the roof, and the 
superior portion of the side walls; the two temporals, both 
squamous and petrous, found at the inferior portion of the side 
walls; the occipital completing the posterior and upper part of 
the roof, constituting the whole of the back wall and a portion 
of the floor; inferiorly and anteriorly, both on the side wall and 
the base; the ethmoid, and filling the middle of the floor, the 
sphenoid. 
The cranium was formed of so many bones, not so much for 
the safety of the mother in the act of parturition, because, from 
