Page:Proceedings of the Royal Society of London Vol 1.djvu/39

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oxalate, forming water; the carbon is saturated with oxygen, forming carbonic acid gas; and a part, if not the whole of the nitrogen of the aetherized gas is separated in the state of nitrogen gas; both which gases are evidently produced after the decomposition of the powder. The mercury is now revived, and converted into vapour, as may be gathered from the immense quantity of caloric extricated, by adding concentrate sulphuric acid to the mercurial powder. On a more minute analysis he finds the proportion of these ingredients in 100 grains of the mercurial powder to be as follows:— Grains.

Of pure oxalic acid . . . . . . . . . . . . . . . . . . . . . . 21-28

Of mercury formerly united to the oxalic acid. . . . 6072

Of mercury dissolved in the sulphuric liquor . . . . 2'00

Of mercury left in the sulphuric liquor after the sparation of the gases.. . . . . . . . . . . . . 2'00 . Total of mercury...... —— 6472 Of nitrous :etherized gas and excess of oxygen . . . . . . . . 14'00 100'00

The following are the principal properties of this singular powder:—it takes fire at the temperature of 368° of Fahrenheit; it 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 when surrounded by atmospheric air; and it detonates loudly, both by the blow of a hammer and a strong electrical shock Its action, though extremely powerful, is however confined within a very limited sphere. It will burst a gun-barrel, though it will not carry a ball to any considerable distance.

Mr. Howard does not fail to caution future operators concerning the experiments they may be tempted to make on this powerful agent, having himself suffered considerably from an instantaneous explosion, produced by pouring six drums of concentrated sulphuric acid upon fifty grains of the powder, which wounded him severely, and destroyed the best part of his apparatus. This uncommon elastic power is ultimately ascribed to the gas and caloric suddenly set at liberty, and to the mercury and some portion of water being converted into vapour.

The paper concludes with some observations on other fulminating powders, where the author acknowledges that he has in vain attempted to communicate fulminlnltating properties, by the mercurial process, to gold, platina, silver, antimony, tin, copper, iron, lead, zinc, nickel, bismuth, cobalt, arsenic, and manganese; mercury being as yet the only metal which he has found to have a joint affinity with nitrous aetherized gas and oxalic acid, or to be capable of combining with nitrous aetherized gas.

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