C 841 ) ^ 
the Arteries and Nerves are,the further they go from the 
Heart and Brain ; whereas there is no difference between 
the Veflels of the Bark of the Root and Trunk : Befides, 
the Veffels of the Bark of (everal Trees, as the Birch, 
Cherry, Peach, &c. run not upwards as they do in the 
Alh, Oak, Elm, Nut, Apple, Pear, &c. but Circular- 
ly round the Superficies of the Tree. And all Bark whofe 
Veflels run upwards, grows thicker as the Tree increafes, 
theoutfide cracking grows Dead, and flicks to the young 
Bark underneath, which is the only living Part of the 
Bark. The contrary is evident in thofe Barks whofe Vef- 
fels run round the Tree; fGr as the Tree increafes the Vet 
fels not being able to Stretch nor Separate from each other, 
muft neceflarily break afunder ; fo that the Old Bark is 
eafily Separated and falls off from the New. Wherefore 
fiich Trees have always a very thin Bark, as is moft evi- 
dent in the Birch Tree, 
And as we (aid of the Bark, that it is produced and 
aourilht from the Trunk of the Tree, fo is it in the Pro- 
duction of the Skin of Animals, which is covered over 
with the Scarf-skin, confiding of Scaly Particles : For 
having examined the Skin of many Animals, it teemed 
to me to be formed by the wondrous interweaving of all 
the extremities of the Veflels that proceed to the extream 
parts of the Body ; from the ends of which, a certain 
matter iflues forth forming the Scales ; the extremities 
terminating at thofe Scales which fo long flick fafl to the 
Veflels, till new ones difplace them ; and once in the 
Skin of a very Fat Dog, I found a great number of 
Fat- globules between the branches of the Veflels that coa- 
ftitute the Skin. 
Thefe Obfervations brought me to Examine again the 
Scales that cover our Bodies, to find if it were poiliWe 
whether they were not formed after the fame manner as 
thofe of Fifties: and indeed each Scale of our Body is 
compofed of a great company of Veflels, interwoven 
il r together 
