( 518 ) 



CHAPTEE XL 



POWDERS WITH CHLORATE BASE. 



1. GENERAL NOTIONS. 



1. BERTHOLLET, after having discovered potassium chlorate, and 

 recognised the oxidising properties so characteristic of this salt, 

 thought of utilising it in the manufacture of service powders. 

 He made several attempts in this direction, but immediately 

 suspended them after an explosion which happened during the 

 manufacture carried on at the Essonnes powder factory, an 

 explosion in which several persons were killed around himself. 

 The same attempt has been revived at various periods, with 

 certain variations in the composition. 



But in every case explosions, followed by loss of lives such, 

 for instance, as those which happened during the siege of Paris 

 in 1870, and at L'Ecole de Pyrotechnie in 1877 happened 

 before long in the course of its manufacture. 



It is thus clear that potassium chlorate is an extremely 

 dangerous substance, which is only natural, because its mixture 

 with combustible bodies is sensitive to the least shock or 

 friction. The catastrophe in the Eue Beranger (see p. 46), 

 produced by an accumulation of caps for children's play- 

 things, containing potassium chlorate, has helped to confirm 

 these ideas. Chlorate powders are, generally speaking, more 

 easily ignited, and burn with more vivacity than black powder. 

 They explode, like the latter, on contact with an ignited body. 

 They are" hardly used at the present day, except as fuses for 

 fireworks, or to produce shattering effects in torpedoes, for 

 instance. A powder of this kind has even been proposed in 

 America as motive agent of forge-hammers or pile-drivers. In 

 this case the cartridge is placed between the head of the pile and 

 the ram, when the explosion drives in the one and sends the 

 other upwards. Their strength is superior to that of nitrate 

 base powders, but less than that of dynamite or gun-cotton. 



2. We shall first state the general properties of chlorated 



