[ "5 ] 



fary. The colour ihould be a greyifh blue, tinged with red, and 

 the texture of the grain firm, but not fo hard as to refift a very 

 forcible preflure from the finger agaixift a board. I am aware 

 that my opinion difagrees with the general ideas of Britifh 

 powder-makers, who prefer a dark blue colour, and an angular 

 grain, thinking that hue and form fufceptible of the readieft 

 inflammation ; but a general deduction from numerous experi- 

 ments has convinced me of their miftake. 



The ftrcngth of powder is frequently impaired by being too 

 precipitately dried ; this I difcovered on examining fomc of the 

 rooms appropriated to that operation, where finding the heat 

 intenfe, I fufpeded its being fufficiently powerful to evaporate 

 the fulphur, which a clofer infpedion proved to be the cafe, as 

 the crevices of the walls and fhelves were filled with flour of 

 brimftone fubhmed by the adion of the fire, from the furface of 

 the grains, precifely where the greateft proportion of this inflam- 

 mable principle is required. The acceleration of the drying pro- 

 cefs has this farther difadvantage, that it leaves the powder moift 

 in the centre of the grain : I fear this pradice, though every way 

 pernicious, is become fo general as to demand the interference of 

 government j the detedion of fuch powder is eafy ; for when 

 frefh from the drying-houfe it will rife to high proof, but being 

 left in the magazine for a month will lower its ftrength at Icaft 

 a fourth : And here I muft obfervc, that in times of peace, when 

 the demand cannot be very prefllng, powder fhould not be proved 

 fooner than two months after being manufadured. 



Q, 2 It 



