MEMOIR 



EXPLOSIYEIESS OF IITRE 



SUMMARY. 



Statement of the Phenomena and Facts of the Great Explosion. — Attributed to Gunpowder — This 

 disproved by competent Witnesses. — Failure of the Chemists employed by the City Government to 

 produce an Explosion by Mixtures of Nitre with Combustibles, and their consequent Report against 

 the explosive Efficacy of Nitre. — Opposing Opinion of respectable Chemists, especially Sillimau 

 and Hayes. — Experiments of the latter, showing that Nitre may explode with Water, confirmed by 

 an Explosion which had happened in the Author's Laboratory. — Illustrative Reference to the Explo- 

 sion consequent, to the Combustion of Potassium upon Water. — Explosiveness of Nitre with Substances 

 containing Water or Hydrogen, ascribed to the Affinity of Water for Bases being at a high Tempera- 

 ture, greater than that of Nitric Acid. — Discrimination between explosive Combinations of which the 

 Ingredients are held in a State of Contiguity by chemical Affinity, and pulverulent Mixtures mechan- 

 ically aggregated ; compression being requisite to Explosiveness in the one Case, but not in the other. 

 — Chemical Affinity, in the Case of Potassium o.Nidized and intensely heated upon Water, performs 

 the Part of mechanical Force in the Explosion of Moisture by the Impact of incandescent Iron. — 

 Nitre exploded with Sugar under incandescent Iron simultaneously struck with a Sledge. — Force of 

 the Impact thus produced, less than that, for an equal Area, resulting from the dancing of 700,000 

 pounds of Merchandise upon 300,000 of incandescent Nitre within the Walls of the exploded Store. — 

 Impossibility of exploding Gunpowder or Gun-Cotton in Vacuo. — Products of the Combustion of 

 these Compounds ascertained and compared ; also their projectile Power, which for equal Weights 

 makes that of Gunpowder to Gun-Cotton, nearly as one to four ; while the gaseous Products are as 

 one to three nearly. 



1. Among the conflagrations by which cities have been more or less devastated, 

 there has been none, it is beheved, of which the phenomena were more awful and 

 mysterious than those of the great fire which took place in the city of New York, 

 on the 19th of July, 1845. 



2. The destruction of two hundred and thirty houses, containing merchandise 

 amounting in value probably to two millions of dollars, made the calamity in ques- 

 tion highly deplorable as a cause of pecuniary loss and embarrassment ; while the 

 characteristics which gave to it an unprecedented rapidity of extension, were of a 

 nature to excite an enduring interest as well as temporary consternation. 



