[ "3 ] 



contributes moft to the decompofition of powder. Believing 

 this pofition, but retaining feme doubts of its being pradicable 

 to produce forcible powder from nitre and charcoal only, I di- 

 reded a fmall quantity to be made, and was agreeably furprizcd 

 to find that fifteen pounds of it projeded a thirteen inch fhell 

 as far as the beft powder compofed in the ufual manner; from 

 hence I conclude that a powder might be made fufiiciently ftrong 

 (when ufed in quantities above ten pounds) with a much lefs 

 proportion of fulphur than the prefent pradice admits of. In 

 cafes where a fmaller charge is ufed, or where a rapid inflam- 

 mation is required, the ufual dofc of fulphur is indifpenfably 

 necellary. 



The procefs of glazing powder is efFcded by attaching caflis, 

 fomething more than half full, to the axis of a water wheel, 

 which turning with velocity, the operation is compleated in a 

 fhort time by the fridion of the grains againfl each other. I 

 found, from a mean of ne2ix Jix hundred experiments, that glazing 

 powder reduces its ftrength about one-fifth if the powder is 

 good, and nearly a fourth if of an inferior quality ; this procefs 

 being more noxious to the force of bad powder than of good, is 

 accounted for, in my opinion, by the greater proportion of duft 

 feparated during the operation from the former than from the 

 latter, as this refiduum is invariably ftronger than the glazed 

 powder from which it has been fcreened. I am confident, how- 

 ever, that it would be a wife meafure was government to adopt 

 the pradice of glazing all high proof powder, and referving it 

 for the garrifons abroad, where it muft remain long in the maga- 



O^ zine, 



