[ 455 3 
arifing, are extremely near the fubduplicate Proportion 
of thofe Quantities of Powder, and this independent 
of the Length of the Piece : Whence it is confirmed, 
that the Elafticity of fired Powder in various Circum- 
ftances, is nearly as itsDcnfity ; and this docs not only 
fuccced in frnall Quantities of Powder, and in (mail 
Pieces, but in the larged likewife, under proper Re- 
ftri&ions; at lead there are Experiments which could 
not be inducnced by this Theory, where the Quantities 
of Powder were above ioo times greater than what 
are ufed by this Author, and in thefe Trials this Cir- 
cumdance takes place to fufficient Exact nefs. 
It is prefumed then, that by this Theory a near Edi- 
mate may be always made ot the Velocities commu- 
nicated to Shells or Bullets by given Charges of Pow- 
der 5 at lead thefe Experiments evince how truly the 
Velocities of frnall Bullets are hereby adigned ; and 
the Author can fhew by the Experiments of others, 
that in a Shell of Thirteen Inches Diameter, impelled 
by a full Charge of Powder, the fame Principle nearly 
holds: It is true indeed, that when the Charge is 
much frnall er than the ufual Allotment of Powder, 
there are fome Irregularities, which are particularly 
mentioned at the End of the 9th Propofition, to which 
Head too, perhaps, mud be referred the Experiments 
made by the Committee on theEffeft of different frnall 
Chambers j but in the cudomary Charges, the Velo- 
cities of Bullets refulting from all the Experiments 
hitherto made, are really fuch as the Theory laid down 
in the preceding Part of this Treatifc requires. And 
it appears, that thefe Velocities are much greater than 
what they have been hitherto accounted : And there 
are Reafons from the Theory to believe, that in Can- 
Nnn non-fhot 
