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HI. Jn Account of- an Experiment touching the different 
T)^njities of the Air^ from the greatefl Natural 
Heat^ to the greatejl Natural Cold in this Climate. 
(By Idr. Fr. Hauksbee, F. S. 
I Took a Glafs Tube about 2 Feet in length, and near 
two tenths Diameter 5 which at about 6 Inches from 
one end, I bent in form of a Syphon, as reprefented by 
the Figure : at whofe end, which was fartheft diftant 
from the Angle, I cemented on a Brafs Screw with afmall 
Perforation in it 3 by which means, when I put a little 
Quickfilvcr into the (horter Leg, 1 could by declining the 
Tube, or longeft Leg, bring it to reft, any where 3 as 
fuppofe at A A. the fuperfluous Air within paffing the 
premention'd Perforation. Then fcrewing a Cap on if, 
the Mercury was detain’d in the fame Place, and pofteft 
in length about half an Inch. In this manner it was 
convey’d into a Wooden Trough, with a Thermometer: 
Then putting in as much warm Water as would cover 
its Ball, the Syphon lying at Bottom in an Horizontal 
O Pofition, 
