68 
Hcemajlatics. 
to drive the Blood thro* the great Artery, and 
its feveral Branches than thro* the Lungs 5 and 
accordingly the left Ventricle of the Heart is 
made much ftronger, thereby to impel the 
Blood with a greater Force than the right 
Ventricle does. 
10. On comparing the different Velocities 
of the Blood in the Mufcles, and in the Lungs 
of a Frog 5 I found that the Blood moves in 
the parallel cylindrical capillary Arteries in the 
ftrait Mufcles of its Abdomen at the rate of 
-^th of an Inch in nine Seconds of time, that 
is at the rate of an Inch in ninety Seconds, 
or one Minute and a half. 
11. But the Blood flowed in the capillary 
converging Arteries of the Lungs with a much 
greater Velocity, viz. -pjh of an Inch in the 
Time of eight beats of a Watch, which beat 
16000 times in an Hour, that is in :j7^th 
Part of a Second. And there being 545.42 
beats in nine Seconds, thefe eight beats of the 
Watch are 4-,!7^th part of the abovementioffd 
nine Seconds; fo that the Velocity of the 
Blood in the Frog’s Lungs was forty three times 
greater than in its Mufcles. 
II. And I obferved that the Motion of it 
thro* the Lungs was fo free, that I could not 
only 
