REGARDED AS A MASS. 115 



comes up behind the front flap, and is tied to the colon and 

 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 scull, 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 apon, or intermix with, 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 

 in 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 Ls 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 process, is knit to the edge of a broad fat 

 membrane, called the mesentery. 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 mesen- 

 tery itself, it is, what a sempstress would call, ''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 



" Ches. Anat. p. 149. 



