C 759 ) 
Not fully fatisfied herewith, I put one Corn of Pow- 
der in a Glafs, and clofing it up with a very fmall hole 
only at the narrow end, which end I placed under the 
Water in the glafs Veffel as before, and firing the Pow- 
der, Co great a quantity of Air was thereby generated, 
as forced out 160 Grains of Water. Now 13 Corns 
of Powder weigh but one Grain • wherefore multiply- 
ing 160 by 13, which makes 2080, we find that Gun- 
powder fired expands it fdf 2080 times, or takes up fo 
many times the Space it did before. 
I cbferved like wife that the Glafs wherein the Pow- 
der was fired would be always filled half full of Water 
immediately after the Explofion, the reafon of which 
I conceived to be the great rarefa&ion of the Air, by 
the Heat of the Fire and (Iroke of the Powder 5 which up- 
on cooling takes up lefs Space, and the Water enters in 
to fill up the reft to prevent a Vacuity. 
From this laft Observation, I concluded that a Bullet 
cannot be fhot with (6 great a Force out of a very long 
Canon, or other Gun, as out of one fomething Sort- 
er : And difeourfing fince with a certain Commander 
Epon this Subjedt, he told me he was once prefent 
when upon a Wager a Cannon of 14 Foot threw a Ball 
much farther than one of 1 8 Foot. 
As to the Reafon, how fo great a quantity of Air 
comes to be generated, tho' I thought of feveral Solu- 
tions, yet I could not fatisfie my felf,- I fometimes 
thought that the Particles of the Air were by the violent 
motion broken and comminuted into fmaller, and fo be- 
tween each Particle a much finer Subftance might be 
placed, but this did not snfwer fo great an Expanfion. 
Upon the whole, I concluded that the greateft Improve- 
ment that can be made in footing, is, ifpoftible, fo 
to order the matter,, that all, or the greateft part of the 
Powder be fired at once,- and when this is efTeikd,, a- 
much lefs quantity will ferve than is now vrfedv 
