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LIII. Some further Observations on a new detonating Sub- 
stance. Ina Letter to the Right Honourable Sir JosEPH 
Banks, Bart. K.B. P.R.S. By Si Humrury Davy; 
22.0. BRS. Ger. BL 
Berkeley-Square, June 20, 1813. 
My Dear Sirgtl HAVE already described, in a letter 
which you were so good as to communicate to the Royal 
Society, a few facts respecting a new detonating compound. 
I shall now do myself the honour of mentioning to you 
some other particulars on the subject. 
I received, in April, a duplicate of the letter in which the 
discovery was announced, containing an Appendix, in which 
the method of preparing it was described, M. Ampere, my 
correspondent, states that the author obtained it by passing 
a mixture of azote and chlorine through aqueous solutions 
of sulphate or muriate of ammonia. [t is obvious, from 
this statement, that the substance discovered in France, is 
the same as that which occasioned my accident. The azote 
cannot be necessary ; for the result is obtained by the ex- 
posure of pure chlorine to any common ammioniacal salt. 
Since I recovered the use of my eyes, I have made many 
experiments on this compound; it is probable that most of 
them have been made before in France; but as no accounts 
of the investigations of M. Dulong on the substance have 
appeared in any of the foreign journals which have reached 
this country, and as some difference of opinion and doubts 
exist respecting its composition, I conceive a few details on 
its properties and nature will not be entirely devoid of in- 
terest. 
I have been able to determine its specific gravity, I hope, 
with tolerable precision, by comparing its weight at 61° 
Fahrenheit, with that of an equal volume of water. 8°6 
grains of the compound, carefully freed from the saline 8o- 
Jution in which it was produced, filled a space equal to that 
filled by 5°2 grains of water, consequently its specific gra= 
vity is 1°653. 
When the compound is cooled artificially, either in water 
or in solution of nitrate of ammonia, the fluid surrounding 
it congeals at a temperature a little below 40° Fahrenheit, 
which seems to be owing to its becoming a solution of chlo- 
rine; for, as I have stated in a paper published in the Phi- 
josophical Transactions, the saturated solution of chlorine 
in water freezes very readily. The congelation of the fluid, 
in contact with the new compound, led me, when I first 
* From the Philosophical Transactions for 1813, part ii. 
Vol, 42. No. 187. Nov. 1613. x operated 
