114 
OF THE ANIMAL STRUCTURE 
comes up behind the front flap, and is tied to the colon ana 
adjoining viscera.* 
9. The septa of the brain probably prevent one part 
of that organ from pressing with too great a weight upon 
another part. The processes of the dura mater divide the 
cavity of the skull, like so many inner partition walls, and 
thereby confine each hemisphere and lobe of the brain to 
the chamber which is assigned to it, without its being liable 
to rest upon, or incommode the neighbouring parts. The 
great art and caution of packing is to prevent one thing 
hurting another. This, in the head, the chest, and the 
abdomen, of an animal body, is, amongst other methods, 
provided for by membranous partitions and wrappings, 
which keep the parts separate. 
The above may serve as a short account of the manner 
m which the principal viscera are sustained in their places. 
But of the provisions for this purpose, by far, in my opin¬ 
ion, the most curious, and where also such a provision was 
most wanted, is in the guts. It is pretty evident, that a 
long narrow tube (in man, about five times the length of 
the body) laid from side to side in folds upon one another, 
winding in oblique and circuitous directions, composed al¬ 
so of a soft and yielding substance, must, without some ex¬ 
traordinary precaution for its safety, be continually displac¬ 
ed by the various, sudden, and abrupt motions of the body 
which contains it. I should expect that, if not bruised or 
wounded by every fall, or leap, or twist, it would be entan¬ 
gled, or be involved with itself, or, at the least, slipped and 
shaken out of the order in which it is disposed, and which 
order is necessary to be preserved for the carrying on of 
the important functions, which it has to execute in the ani¬ 
mal economy. Let us see, therefore^ how a danger so seri¬ 
ous, and yet so natural to the length, narrowness, and tubu¬ 
lar form of the part, is provided against. The expedient 
is admirable, and it is this; the intestinal canal, through¬ 
out its whole progress, is knit to the edge of a broad fat 
membrane called the mesentery. [PI. XXII. fig. 2.] It forms 
the margin of this mesentery, being stitched and fastened 
to it like the edging of a ruffle: being four times as long as 
the mesentery itself, it is what a sempstress would call, 
“puckered or gathered on” to it. This is the nature of 
the connexion of the gut with the mesentery; and being 
thus joined to, or rather made a part of the mesentery, it is 
folded and wrapped up together with it. Now the mesen¬ 
tery, having a considerable dimension in breadth, being in 
* Ghes. Anat. p. 149. 
