348 APPENDIX. 
Mercury with a little Spirit of Turpentine, 
which was tinged with Indigo: The Viol 
and Tube were let down into a large Bomb 
full of Water, which was placed under a 
Cyder Prefs 5 then there was put into the 
Orifice of the Bomb a well turned Plug of 
Holly Wood, which was impelled fo forcibly 
into the Bomb by the Screw of the Preft^ 
that Water ouzed through the Pores of the 
Plug, notwithflanding it had been dipped in 
melted Cement made of Bees Wax and Tur- 
pentine. When I took the mercurial Gage 
out of the Bomb, I found the tinged Tur- 
pentine had rifen fo high as to have com- 
prefiTed the included Air within the Space 
of o. II Inch of the Top of the Tube; that 
is, the 38. 44th part of its Capacity*, (o that 
the included Air was comprefTed with 37. 44 
Atmofpheres, equal to the Preffure at 1233. j 
Feet or 203. 5) Fathom depth in the Sea: So 
that the Denfity of this Air was to that of 
Water as i to 22. 7. 
16. Air when thus greatly compreffed, has 
not been obferved either to enter the Mer- 
cury in the Gage, nor to pafs through the 
Pores of the Glafs ; nor has it been found to 
be fixed by any known Degrees of Com- 
preffure 
