5 2 Hcemajlatks. 
ferved to be of feveral Sizes from t to f of the 
Arteries whence they rofe, and the fucceed- 
ing ones finer and finer to nearly 77'^th part 
of an Inch, that is fo fine, that only fingle 
^ Blood globules can pafs them into the Veins ; 
here therefore fo vifeid a Fluid as the Blood 
muft needs meet with a very great Refiftancc. 
10. If we compare the Area of the Orifice 
of the brafs Pipe, which was in this Experi- 
ment fixed to the defeending Aorta^ with the 
Sum of the Areas of all the large mefenteric 
Arteries juft before they fubdivide into Branch- 
es, which immediately enter the Coats of the 
Guts, and alfo with fome of the Areas of the cut 
Orifices of the above-mentioned converging 
Arteries, they are as follow, *viz. 
1 1. The Area of the Orifice of the brafs Pipe 
was 0.0 J7 fquare Inch, taking a mean Diame- 
ter of one of the mefenteric Arteries to be 0.0 6* 
Inch, its Area 0.0028, and counting 82.8 of 
thefe in i i+J Feet Length of the Bit Gut, the 
Sum of all their Areas will be 0.234 Inch. 
12. Taking alfo the Diameter of one of 
thefe Arteries at their firif entering the Guts 
to be equal to 0.02, its Area will be 0.0003 14, 
and the Sum of 724.25 of thefe Areas in 
ii-ft Feet length of Gut will be c.227. 
14. And 
