{. ioo8 ) 
tie difference from Blood, I found the Specifick Gra- 
vity of cold Blood to be 
Exp, XIV. /iug. 6 th. 1718. The laft Experiment 
being repeated in the fame manner as the Year be- 
fore, the Specifick Gravity of cold Blood was again 
found to 1055'. 
£x/>. XV. 14th. 17*9. The Arterial Blood, 
from w'hich the Serum w^as afterwards drawn off for the 
iith Experiment, being w^eighd in the fame manner, 
it’s Specifick Gravity was 1051, 
As this Arterial Blood and it’s Serum, differ no more 
in Specifick Gravity from Venal Blood and Serum, 
than the feveral Portions ot thefe do from one ano- 
ther, it’s plain, that the difference in this refped be- 
tween Arterial and Venal Blood is wholly inconfide- ' 
rable. The Animal Oeconomy indeed teaches u% v 
that the Serous Liquor is perpetually drawing off . 
from the Arterial Blood by the ieveral Secretions, but 
as the quantity feparated in one Circulation is very ♦ 
fraall, the Blood muft arrive in the Veins nearly of 
the fame denfity, as when it runs through the Arte- 
ries. 
In the 15th Experiment we obferv’d, that the Blood 
altered it’s Specifick Gravity upon cooling from icyf3 ^ 
to 1055; ^t:otn which we may infer, that if the Blood ' 
made ufe of in the nth Experiment had beenfuffered 
to Band till ir was cold, it’s Specifick Gravity would 
have been 1053 5 wherefore, taking a Medium be- 
tween the four laft Experiments, w'e may allow the 
Specifick Gravity of cold Human Blood to be 1054. 
The difference of 14 Parts in a 1000, between this 
and the Specifick Gravity determined by Mr, Boyle, is 
eafily accounted for, if we confider, that that Gentle- 
man did not make ufe of a Veflel with a narrow 
Neck, as plainly appears from the circumflances men* . 
tioned 
it 
