14 ll^mafiatics. 
the Head, a Glafs Tube, which was four 
Feet, and two Inches long. 
5. The Blood rofe in it, in three or four Se- 
conds of Time, about a Foot, and then was 
ftationary for two or three Seconds ; then in 
three or four Seconds more, it rofe fome- 
times gradually, and fometimes with an un- 
equally accelerated Motion nine Inches more, 
on fmall Strainings of the Mare : Then upon 
greater Strainings it rofe about a Yard, and 
would fubfide five or fix Inches : Then upon 
a larger Strain or Struggle of the Mare, ic 
rofe fo high, as to flow a little out at the 
Top of the Tube ; fo that had the Tube been 
a few Inches higher, it would have rifen 
probably to that Height. 
4. When the Mare ceafed to ftrain and 
ftruggle, the Blood fubfided about eighteen or 
twenty Inches ; fo the Return of the Blood into 
the Vein was not hindred by the Valves 5 which 
I have alfo obferved in other Parts where 
there arc Valves, tho* fometimes they abfo- 
lutely hinder the Return of any Fluid. 
5. The Diameter of the Brafs Pipe and 
Tube which were fixed to the Vein, were 
nearly one feventh of an Inch : The Diameter 
of the Jugular Vein about half an Inch. 
6 . Then 
