OQO FULMINATING MERCURY. 



formed ; otherwise, when the mother liquor is abundant, it often 

 becomes grey, and is re-dissolved." 



" Several trials of the mercurial powder were afterwards nn 'e 

 at Woolwich, in conjunction with Colonel Bloomfield and 

 Cruickshank, upon heavy guns, carronades, &c. from which Mr. 

 Howard generally infers, that any piece of ordnance mi^ht be 

 destroyed, by employing a quantity of the mercurial powder, 

 equal in weight to one.half of the service-charge of gunpowder ; 

 and, from the seventh and last experiment, we may also conclude, 

 that it would be possible so to proportion the charge of mercurial 

 powder, to the size of different cannons, as to burst them without 

 dispersing any splinters. But the great dang r attending the use 

 of fulminating mercury, on account of the facility with which it 

 explodes, will probably prevent its being employed for that pur- 

 pose. 



" In addition to the other singular properties of the fulminatiug 

 mercury (says Mr. Howard), it may be observed, that two ounces, 

 inflamed in the open air, seem to produce a report much louder 

 than when the same quantity is exploded in a gun, capable of re. 

 listing its action. Mr. Cruickshank, who made some of the pow- 

 der by my process, remarked, that it would not inflame gunpow- 

 der. In cousequence of which, we spread a mixture of coarse 

 and fine-grained gunpowder upon a parcel of the mercurial pow- 

 der; and after the inflammation of the latter, we collected most, 

 if not all, of the grains of gunpowder. Can this extraordinary 

 fact be explained by the rapidity of the combustion of fulminating 

 mercury ? Or is it to be supposed (as gunpowder will not explode 

 at the temperature at which mercury is thrown into vapour) that 

 sufficient caloric is not extricated during this combustion ? From 

 thf late opportunity I have had of conversing with Mr. Cruick. 

 shank, 1 find that he has made many accurate experiments on gun. 

 powder ; and he has permitted me to state, that the matter which 

 remains after the explosion of gunpowder, consists of potass, 

 united with a small proportion of carbonic acid, sulphate of pot- 

 ass, and a very small quantity of sulphuret of potass, and uncon- 

 sumed charcoal. That 100 grains of good gunpowder yielded 

 about fifty-three grains of this residuum, of which three are char- 

 coal. That it is extremely deliquescent, and when exposed to the 

 air, soon absorbs moisture sufficient to dissolve a part of the 

 alkali; in consequence of which the charcoal becomes exposed, 



