( 527 ) 



CHAPTER XII. 



CONCLUSIONS. 



WE have now reached the end of our task. We have submitted 

 a general theory of explosive substances, based on the know- 

 ledge of their chemical metamorphoses, and of the heat of 

 formation of the compounds which contribute thereto, that is to 

 say, entirely deduced from thermo-chemistry. We will sum- 

 marise the fundamental results of this study, both as regards 

 general notions and as regards the particular definition of ex- 

 plosive bodies. 



Meanwhile, industry, in this respect, as in many others, has 

 received an unexpected impetus as a consequence of the 

 theoretical discoveries of organic chemistry; discoveries which 

 have facilitated the manufacture at will of a multitude of ex- 

 plosive substances hitherto unknown, and whose properties 

 vary ad infinitum. 



Empiricism, however, was still the only guide in forecasting 

 with accuracy the properties of each of these substances at the 

 time when thermo-chemistry came to our aid, enabling us to 

 establish the general principles which define new explosive 

 substances according to their formulae and their heat of forma- 

 tion. Thermo-chemistry thus marks the limits which we can 

 hope to reach in practice, and it lends the light of rational rules, 

 by which alone the subject is capable of being fully developed. 



It is this transformation of the empirical study of explosive 

 substances into a strict science, based on thermo-chemistry, that 

 the author has been pursuing since 1870, and of which the 

 present work is the most advanced expression at the present 

 state of our knowledge. 



1. SUMMARY OF THE WORK. BOOK I. 



1. The sudden development of a considerable expansive force 

 characterises explosive substances. By this means they effect 

 enormous mechanical work, which industry would be unable to 



