VOL. XC.] PHILOSOPHICAL TRANSACTIONS. 66l 



Should this inflammable gas prove not to be a hydrocarbonate, I shall be disposed 

 to conclude, that it has nitrogen for its basis : indeed, I am at this moment inclined 

 to that opinion, because I find that Dr. Priestley, during his experiments on his de- 

 phlogisticated nitrous air, once produced a gas which seems to have resembled this 

 inflammable gas, both in the mode of burning, and in the colour of the flame. 

 After the termination of the common solution of iron in spirit of nitre, he used 

 heat, and got, he says,* " such a kind of air as I had brought nitrous air to be, 

 by exposing it to iron, or liver of sulphur ; for, on the first trial, a candle burned 

 in it with a much enlarged flame. At another time, the application of a candle to 

 air produced in this manner, was attended with a real though not a loud explosion ; 

 and, immediately after this, a greenish coloured flame descended from the top to the 

 bottom of the vessel in which the air was contained. In the next produce of air, 

 from the same process, the flame descended blue and very rapid, from the top to 

 the bottom of the vessel." 



These greenish and blue coloured flames, descending from the top to the bottom 

 of the vessel, are precisely descriptive of the inflammable gas separated from the 

 powder. If it can be produced with certainty by the repetition of Dr. Priestley's 

 experiments, or should it by any means be got pure from the nitrous etherized gas, 

 my curiosity will excite me to make it the object of future research ; otherwise, I 

 must confess, I shall feel more disposed to prosecute other chemical subjects : for, 

 having reason to think that the density of the acid made a variation in the product 

 of this gas, and having never found that any acid, however dense, produced an im- 

 mediate explosion, I once poured 6 dr. of concentrate acid on 50 gr. of the powder. 

 An explosion, nearly at the instant of contact, was effected : I was wounded severely, 

 and most of my apparatus destroyed. A quantity also of the gas I had previously 

 prepared, was lost by the inadvertency of a person who went into my laboratory 

 while I was confined by the consequences of this discouraging accident. But should 

 any one be desirous of giving the gas a further examination, I again repeat, that as 

 far as I am enabled to judge, it may with safety be prepared, by pouring 3 dr. of 

 sulphuric acid diluted with the same quantity of water, on 50 gr. of the powder 

 and then applying the flame of a candle till gas begins to be extricated. The only 

 attempt I have made to decompose it, was by exposing it to copper and ammonia; 

 which, during several weeks, did not effect the least alteration. 



§17.1 shall now conclude, by observing, that the fulminating mercury seems to 

 be characterised by the following properties. It takes fire at the temperature of 368 

 Fahrenheit ; explodes by friction,-^ by flint and steel, and by being thrown into 

 concentrate sulphuric acid. It is equally inflammable under the exhausted receiver 

 of an air-pump, as surrounded by atmospheric air; and it detonates loudly, both by 

 the blow of a hammer, and by a strong electrical shock. Notwithstanding the 



* Priestley on Air, vol. 2, p. 88. Birra. 1790- 1 Consequently it should not be inclosed in a bottle 



with a glass stopper. — Orig. 



