CHEMICAL SCIENCE. 251 



EXPERIMENTS RESPECTING THE EXPLOSIVE CHARACTER OF CER- 

 TAIN COMPOUNDS. 



In the month of September, 1854, during an extensive conflagration at 

 Newcastle, England, a warehouse, containing a large quantity of nitrate of 

 soda, sulphur, and other materials, took fire. Water being thrown upon 

 the burning mass, a tremendous explosion occurred, killing and wound- 

 ing many persons, and destroying all the adjacent structures. Some 

 doubt prevailing respecting the cause of the explosion, a number of inter- 

 esting experiments were made before the coroner's jury, under the direc- 

 tion of Mr. Pattinson, and Captain Du Cane, of the Royal Engineers, who 

 was detailed by government for the investigation. Under their direction, 

 an iron pot about 12 inches in diameter was sunk into the earth, in such 

 way that the rim was on a level with the surface. Into this pot were put 

 about 9 Ibs. of nitrate of soda and 6 Ibs. of sulphur, which were ignited ; 

 and when burning at their greatest fury, and throwing up a brilliant flame, 

 a quantity of water, little more than a pint, was projected into the vessel 

 by means of a long iron spout, so placed that the water fell into the fire 

 from an angle of about 30 degrees. As soon as the water touched the 

 incandescent mass a loud report was heard ; and almost before it could be 

 remarked, another and much louder explosion followed. The experiment 

 was repeated, and this time with more instantaneous effect, and the explo- 

 sion occurred with greater violence, as if the noise of the two former 

 explosions were on this occasion thrown into one. Most of the jurymen, 

 who, like every body else, kept carefully under shelter while the experi- 

 ments were going on, now expressed themselves satisfied ; but Captain 

 Du Cane and the coroner expressed a wish to see the effect of an explosion 

 when a weight was put over the top of the pot. Mr. Pattinson at first 

 objected to this, from the danger that might result both to the persons of 

 the spectators and of the surrounding buildings ; but on its being suggested 

 that the experiment might be tried in an open field, which would afford 

 room for persons to remain at a safe distance and yet witness the explosion, 

 he consented. The whole party then moved off to w T here a drift- way or 

 mine had been carried for some distance into the face of a steepish bank. 

 The pot was sunk at the entrance to the mine, upon the level ground. 

 The spout from, which the water was to be poured was placed at a rather 

 lower elevation than before, up the covered way, where one of Mr. Pattin- 

 son' s coadjutors was hardy enough to station himself, while all the rest 

 retreated to a safe distance. On this occasion there was the usual quantity 

 of nitre and sulphur placed in the pot, and about five or six cwt. of clay 

 and bars of iron were placed over it, but so as to allow a free passage for 

 the water. When all had retreated, the water was poured, but the result 

 was a disappointment ; whether the water was not poured with sufficient 

 steadiness, or whether, as is most likely, the heat of the nitre which only 

 burned a few minutes had been allowed to go down before the experi- 



