( > 
termine, upon comparing their Obfervations, which of 
thofe Explolions each of them fee at the fame Time ^ 
and thereby the Difference in Longitude of thofe Pla- 
ces would be exadly had, as above. It would, how- 
ever, be worth the While, this Way, to try whether 
fuch common Meteors are difcharged, at any confiderable 
Height above the Clouds, and how far, and whether 
they differ much from one another in their Heights. 
But thefe Speculations I leave, Sir, to your better 
Judgment, either to improve the Hint, if it deferves it, 
or if not, entirely to fupprefs it ; and in either Cafe 
remain 
\ Tours, 6cc. 
VI. An Attempt made before the Royal Society, to 
P?ew how Dayiips^ or foul Air, may be drawn out 
cf any Sort of Mines, dec. by an Engine cow- 
triVd by the <S^yerend J. T.* Defaguliers, 
L. L. D. and F. R. S. 
/ / • 
T he Engine reprefented by the Model, confifts of 
a Triple Crank working 3 Tumps, which both 
fuck and force Air, by Means of 3 Regulators, and are 
alternately apply’d to drive Air into, or draw it from 
any Place affign’d, thro’ fquare wooden Trunks ^ which 
being made of flit Deal, and 10 Inches wide in the In- 
fide, are eafily portable, and joyn’d to one another 
without any Trouble. 
Experiment I. I fill’d a tall cylindrkk Glafs 
with the Steams of a burning Candle and burning Brim- 
ffone Matches, in fuch Manner that a lighted Candle 
A a a X would 
