( 468 ) 



CHAPTER IX. 

 DIAZO COMPOUNDS AND OTHERS. 



1. SUMMARY. 



WE shall give in this chapter the observations and calculations 

 relative to various explosive compounds, such as mercury 

 fulminate and diazobenzene nitrate, both belonging to the 

 group of diazo compounds, the acid mixtures formed of nitric 

 acid associated with an organic compound, which is generally 

 already nitrified, the perchloric ethers and mercury and silver 

 oxalates. This list might be made much longer in theory (see 

 p. 368 and the following), but experimental data and practical 

 applications would be wanting. 



2. MERCURY FULMINATE. 



1. The analysis and mode of decomposition of this body have 

 been given (p. 297) 



2. This reaction liberates + 114-5 Cal. at constant pressure 

 for 284 grms. ; the mercury being supposed gaseous, + 99'1 Cal.; 

 or, for 1 kgm., 463 Cal. or 349 Cal. 



3. The formation from the elements absorbs 62 '9 Cal. for 

 284 grni., or - 221'5 Cal. for 1 kgm. 



4. The total combustion by free oxygen 



C 2 N 2 Hg0 2 + 2 = 2C0 2 + Hg + N* liberates + 250'9 Cal., 



or, the mercury being gaseous, + 235 -5 Cal. 



5. The density is equal to 4 -43. 



6. Pure fulminate may be kept for an indefinite length of 

 time. Water does not affect it. It explodes at 187, and also 

 on contact with an ignited body. 



It is very sensitive to shock and friction, even that of wood 

 upon wood. When used in a cannon, it bursts it, without the 

 projectile having time to displace itself. However, it may be 



