( iiei ) 
That if the Humane Spermatick Jrterks were ContOrte^> 
as in Suadrfipeds^ before they reach their Teftes^ the Aper- 
tures in the Abdommd Mujcles of Mm miift be much larger 
than they nov/ are, and would frequently let the Intejiines 
defcend into the Scrotum 3 which we know neverthelefsof** 
ten happens : inch Ruptures (as they are calFdJ are not fo 
Incident to ^adrupeds^ tho the Paffages for their Spermii-* 
tick VeiTels ( through thdv Abdominal Mufcks^ are nrjch 
wider than in Men^ becaufe the pofition of the Trunks of 
their Bodies is Horizontal^ and their Inteftines therefore 
cannot prefs on the procefles of the Peritondsm^ as ia Mm 
who are B.r0, 
Befides thefe Artipces in difpofing the Trunks of Arteries^ 
I doubt not but much more will be Detected by the Inqui- 
fitive : In the mean time, I fttall, at prefent, purfue the 
Thread, and defcribe the Extremities of the Arteries, with 
their Qmmmications with the Feins^ and afterwards pro- 
duce fome Inftances of the Art of Nature in conveying the 
Refluent- Blood to die He^^r^, 
After the Circulation of the Blood through, the Heart, 
Lung3,and large Blood VefTelSjWas demonftrared by Dr Ear- 
vey^ it was only gueft how the exiremities of the Arteries 
tranfmitted the Blood to the Veins^ till Mr LewenhoecU^ 
Micro/copes had difcovered the continuations of the Extre- 
mities of thofe Veflels in Fi/B, Frogs, &c, vAyich is now 
commonly (hewn by Microfiopes made by other Ha??ds : see thmpw^ 
Yet there are not wanting who doubt of the like^* J'^'^^*'^^^' 
Continuations of the Extremities of Arteries and Veins in 
Human Bodies and ^uidrupeds ^ fince thofe Animals it has 
hitherto been feen in ( to any fatisfaftion, as Mr Leiven- 
hoeck confeffcs) have been either inch t'lfJ), or of tbe Am- 
phibious kjnd, that hiive but One Ventricle in their Hearts, 
and their Blood aftually cold, except in Bats, in which ic 
appears very obfcurely : Add to this, that the Blood in 
thofe Creatures does nor Circulate with fuch Rapidity as 
"in Animds who^iQ He.irrs liavc T-iwo Fentrirles. For all Ani- 
niab\ 
