Haniajlatics. i y j 
exerts its Strength ; I thought it might not be 
a iifelefs Enquiry to examine the Strength of 
the Coats of thofe Veffels. 
2. I poured into an inverted glaft Syphon 
(pme Mercury, fo as to have the fliortefl: Leg, 
which was hermetically fealed, filled within 
four Inches of the Top : To the other open 
end of the Syphon I fixed by means of a 
brafi Pipe, one end of the right carotid Ar- 
tery of a fmall Spaniel Dog, and to the other 
end of the Artery was fixed a condenfing 
Syringe. Then placing the Artery in Wa- 
ter, to fee whether it leaked, I impelled Ait- 
in to fuch a Degree, as made the Mercury com- 
prefs the Air between it and the fealed Top of 
the Tube into fo fmall a Compafs, as (hewed 
by Eftimation, the Force to be equal to a Co- 
lumn of Water a hundred and ninety Feet high, 
or equal to the Weight of 5.42 Atmofpheres ; 
with this Force the Artery burft at once, but 
no Air pafled thro* its Coats before it burft. 
5. The Diameter of this Artery being o.i 
Inch, the Circumference is 0.514, the whole 
Surface of an Inch Length of the Artery will 
be 0.314 of a fquare Inch: Now a Column 
of Water whofe Bafe is a fquare Inch, and its 
Height a hundred and ninety Feet weighing 
8 
