a85 Antiijuih- of the 'Earth. 



tatcd had paffl-J through, was put on paper, and, for expe- 

 dition, laid in four looie parcels, (each of which, when dry, 

 would have weighed about thirty grains,) on a tile one inch 

 and a half thick and eisiht inches fquare, which had been 

 previoufly heated to a degree a little above what could be 

 borne bv the hand. The tile wa.- placed on a table, and left 

 without fartlh-T notice, to allow the powder to become dry. 



At the end of about half an hour the whole of it exploded, 

 making a report equal at leail to that of the difcharge of a 3^ 

 pounder, as declaa-d byaHaval lurgeon then prefent. 'I'he tile 

 was (hivered into a number of pieces, and broken quite thrpugh 

 ihc middle; two panes of a window, at the diliauce of about 

 eight inches from the tile, were alfo Ihivered ; one of which 

 was oppofite, and the other immediately above it; but none 

 of the adjoining fquares of glafs were broken. On another 

 fide, at the dillance of about two feet from the tile, flood a 

 frame contai;»ii>g bottles of fpecimens of chemical prepara- 

 tions, not one of which was broken ; nor did any of the pupils 

 iutfer, who were httinij; on a form only three feet from the 

 powder which ex-jflodcd. — The whole of the room was filled 

 with thick white fumes; and the windows were covered with 

 quickfilver, depofited from the exploded powder. 



I. The above accident fliows that the mercurial prepara- 

 tion cannot be emploved for throwing projectiles like gun- 

 powder, the mode of agency of the exploiion being on quite 

 diflerent principles, as is evident from what is above related ; 

 pSrticulaily in the fracturing of the thick tile, and the very 

 little diftance to which the concuffion of the air was propa- 

 gated. 



^ 2. ft appears that the fulminating mercury is calculated 

 for fliiverine rocks or larire Hones by its exploiion. 



3. From the Compararively low temperature at which the 

 powder exploded, it may be employed for certain deflruc- 

 tive purpofes in time of war, by being coniincd in vefl'els that 

 are liable to be heated. 



4. From the almoll Infinite velocity with which a train of 

 this powder may be fired, it is calculated for fetting on fire 

 thing* which cannot be effected by a train of gunpowder *. 



ANTiaUITV OF THE KAllTH. 



In a former Number we mentioned the French having 

 found in Egypt, on ''omeof the anticnt monuments, different 

 ti'i;ures of i!ie zodiac, which, fuppoiing ilieui to have been 

 orit^iually formed when the heavens had a correfponding pofi- 



• Co-iiiminic:iro(l by Wr';. R. Lowry, a piifiil of Dr. PeaiTon. — For a 

 further account t,t' tliis powdtr, we htg to refer our rcatleri to Mr. How- 

 ard's piper, ^ivta ill a preceding volume. 



tion. 



