AMMONIUM PICRATE. 467 



o mi 305 atm. ... ,, 



8. The permanent pressure = - 7 rr> Wlt ^ tne usual 



n = 0'17 



exception. 



n mi .T_ ^ T 9050 atm. 



9. The theoretical pressure = - - . 



It is higher than that of potassium picrate, whether pure or 

 mixed with potassium chlorate or nitrate. 



10. The Brugere powder is, in fact, formed of ammonium 

 picrate and potassium nitrate. It contains 54 parts of picrate 

 and 46 of saltpetre. Here combustion is not total, and the true 

 reaction is therefore imperfectly known. 



This powder is only slightly hygroscopic: it is stable, and 

 makes little smoke. Its strength is double that of black powder 

 weight for weight. 



11. On account of its fusing properties, ammonium picrate 

 can also be employed in fireworks. 



For example, this salt mixed with barium nitrate gives green 

 fires. 



DesignoUe powder ... 48 



C Ammonium picrate ...... 25 



Brugere powder < Barium picrate ......... 67 



(Sulphur ............ 8 



Mixed with strontium nitrate it gives red fires. 



Ammonium picrate ............... 54 



Strontium nitrate ............... 46 



None of these proportions correspond to total combustion. 



2H2 



