MODERN EXPLOSIVES 27 



verting the powder into larger masses, this being accom- 

 plished either by granulating it with a solution of collodion 

 cotton in ether-alcohol, as in the earlier forms of melinite, 

 or by fusion, which takes place some twenty degrees above 

 the boiling point of water, and casting directly into the 

 shell, as in lyddite and possibly the melinite of the present 

 day. In any condition perfect detonation would yield 

 only colorless gaseous products rich in carbon monoxide, 

 but the bursting of a lyddite shell is frequently accom- 

 panied by a yellow smoke, probably formed by undecom- 

 posed acid in the form of vapor. The shells appear to 

 burst in two distinct ways, in one case giving a sharp, 

 powerful explosion with enormous concussion and no yel- 

 low smoke, and the other a heavy report with the yellow 

 smoke, the two results appearing to be due to perfect de- 

 composition in the first instance, while in the second partial 

 decomposition only probably occurs. 



Various mixtures of picric acid or its salts, together with 

 some oxidizing agent, have been used from time to time, 

 Abel's powder consisting of ammonium picrate, potassium 

 nitrate, and a small quantity of charcoal. 



It is impossible to deal with the numerous other explo- 

 sives which are largely in use in such a survey as this, and, 

 therefore, attention has been confined to those which play 

 the most active part in modern warfare. 



