[ 44 ? ] 
compofed on the Time of the Progrefs of the Fire 
amongft the Grains, and the different Modifications 
which the Force of Powder did thence receive; and 
it has been generally conceived, that the proper 
Lengths of Pieces were determinable from this Prin- 
ciple ; “ That they fhould be long enough to give 
“ Time for all the Powder to fire/' 
But the Author being fatisfied, that no fuch regular 
and progreflive Steps could be obferved in the Ex- 
plofton ; and having found, that by loading with a 
greater Weight of Bullet, and thereby aimoft doubling 
the Time of the Continuance of the Powder in the 
Barrel, its Force received but an inconftderable Aug- 
mentation; and finding too, that doubling or trebling 
the ufual Charge, the Powder thus added always 
produced a correfpondent Effed in the Velocity of 
the Bullet ; and difcovering likewife in a Piece near 
Four Feet in Length, charged with an ufual Charge 
of Powder, that the Velocity communicated to the 
Bullet, during the Firft Three Inches of its Motion, 
was full half the Velocity which it acquired in its 
whole PafTage through the Barrel, and that the Elafti- 
city or Force of the Powder, in the Firft Three Inches 
of its Expanfton, was, at a Medium, near Eight 
times greater than in the laft Two Feet of the Bar- 
rel ; he concluded from all thefe Circumftanccs, that 
the Time employed by the Powder in taking Fire 
was not neceffary to be attended to in thefe Com- 
putations; but that the whole Mafs might be fup^ 
pofed to be kindled, before the Bullet was fenfibly 
moved from its Place. 
And the Experiments reported by the Committee 
are the ftrongeft Proofs, (as far as they extend) that 
M m m 2 Powder 
