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coniprefled or collapled, as we find is the cafe with blood-veflels, 

 when the flefli that inclofes them becomes dry. 



Fig. 38, BCDEF, reprelents this fmall Nerve, the multitudes 

 of velTels compofing which are cut tranfverfely, and in which the 

 hnes or ftrokes denote the cavities or orifices of thofe veflels. Tliis 

 Nerve is furrounded, in part, by five other Nerves, reprefented in 

 the figure by G G G G G, but in thefe I have only reprefented their 

 external coats or membranes, omitting the velTels they contain within 

 them. At four places in the fame figure, namely, at B N C, CH 

 ID, EKLF, and AFM, are reprefented particles of fat, witli 

 which particles I have fometimes fcen a fmall Nerve wholly fur- 

 rounded : but in lean animals I apprehend the Nerves are only fepa- 

 rated from each other bv their membranes ; whence it follows that 

 the juices deltined to form themlelves into fat, when dillributed 

 through the body, will inlinuate themfelves between the Nen-es ; 

 and, in forae part of this fame colledlion of Nerves, of but a few 

 hairs' breadth, I faw feven fmall Nerves, and no fat between them. 



After this, I purfued my difie^lion of the fpinal marrow, until 1 

 could difcover the parts extended lengthways in it ; a fmall portion 

 of which fpinal marrow, as far as art can imitate Nature, I have 

 caufed to be reprefented in Jig. 39, MNOP. I alio made feveral 

 tranfverfe fetlions of this fpinal marrow, and at length, with great 

 pleafure, I faw its component parts to be placed exadlly in the man- 

 ner reprefented in Jtg. 38, except that they appeared rather larger 

 to my eye than here appears. Moreover, in many places I could fee 

 the light of the fun through the orifices of the veflels which I had 

 cut acrofs, and I pointed out the fame to the limner ; but as the ob- 

 jeft, in all other refpe(51:s, perfectly agreed with ^g. 38, I did not 

 think it necelTary to make a frefti drawing. 



While I was feparating the ftrong outer coat which inclofes the 

 fpinal marrow, from the marrow itfelf, I faw many minute Nerves, 

 and, in different places, take a courfe out of the fpinal marrow ; 

 fome of thefe were fo minute, that what I had at firll taken for a 



Vol. II. a q 



