( 100 ) 

 becaiifc all tranfparent particles, which are not fo conneded toge- 

 ther that the light can pafs through them in a ftraight line, and do 

 not conftitute as it were an uniform body, muft exhibit a white ap- 

 pearance to the eye, as I have fliewn in * another place. Thefe ir- 

 regular globules were lb clofely joined, that when I endeavoured to 

 feparate them, fome of them llretched out, and became twice as 

 long as broad, and they appeared to me joined in the manner of 

 net-work : upon obferving which I began to conlider whether the 

 fmallcit blood-veflcls, ifluing out of the corticle, might not be again 

 divided into fmaller branches, and many of them furround thefe 

 globules, or give way to them, as we see the small f horizontal vef- 

 ftls in fome kind af wood give way to the perpendicular veflels, and 

 take a circuit round the half of their circumference. This opinion 

 of mine, that many of thefe irregular globules arc furrounded by 

 fmall veflels, was confirmed, -when I faw many of the laid velTels 

 bright in the middle, and bearing fomething of a dark colour at the 

 fides ; and ftill more, when, upon breaking the globules, I found 

 many fmall fibrous parts which feemed to be veflels lying among 

 them. 1 alfo often faw parts of the medullary fubftance of the 

 Brain of the fame figure, as if we were to behold a fifherman's net, the 

 threads of which can eafily be extended any way, and that between 

 each fpace of the net (which fifhermen call a mefli), 'a very flexible body, 

 in fhape of a ball, was placed, which would aflume either a round 

 or an oblong form, as the net was drawn one way or the other. 

 And to fuch a net I compare the multitude of minute veflels in the 

 medullary fubftance of the Brain, and the balls to the irregular glo- 

 bules I have mentioned. The other parts of the medullary fub- 

 ftance confifted of an almofl; infinite number of excefflvely minute 

 globules, and a clear thin matter, which laft I conje<9:ured had 

 iflued from the wounded veflels, and alfo that fome of the veflels 

 themfelves might have been diflblved into it, 



* See Vol. I. p. 184, Addition by the Tranflafor. 

 » This may be fcen in Vol. 1. Plate 1. fig. 1, at the Letters E E £. Translator. 



