ON EXPLOSIONS IN CHEMICAL LABORATORIES. 253 
the distillation of phosphorus, in consequence of an incau- 
tious experiment. When the development of the combus- 
tible gas and the distillation were in full operation, Mr. 
TrommsdorfF was about showing to his pupils that the gas 
was combustible ; for this purpose, he approached a lighted 
match to the receiver, which contained water, but at the 
same moment the iron cupola, with which the furnace was 
covered, together with the fire pipe, were blown off with 
a loud report, and much damage was done to the appa- 
ratus. The probable cause of this explosion, was, that 
over the surface of the water in the receiver, atmospheric 
air was contained, which had mixed with the phosphuretted 
hydrogen, and formed an explosive mixture. 
That very fatal explosions often take place in operations 
with nitre, is well known, and easily explained ; but only 
one case has occurred in a pharmaceutical laboratory. A 
pharmaceutist had to make Jintimonium diaphoreticum, 
and for this purpose put a crucible in a furnace, between 
red-hot coals, and then gradually introduced a mixture of 
powdered sulphuret of anttmony and nitre, without wait- 
ing for the deflagration, which did not immediately occur, 
as the crucible had not become hot. When all the powder 
had been introduced, an explosion took place, by which he 
was dreadfully wounded. 
Chlorate of potash is far more dangerous than nitre. The 
accident which happened in 1817, in Munich, in conse- 
quence of the incautious treatment of a mixture of chlorate 
of potash, sulphur, sugar, and cinnabar for lucifer matches, 
will be remembered by many: (Repert. fur der Pharm. lii, 
119 — 126.) In fusing chlorate of potash for the evolution 
of oxygen and the production of perchlorate of potash, the 
greatest care is required to prevent any combustible matter 
coming in contact with it. This is proved by the following 
case. An apothecary intending to develop oxygen from 
chlorate of potash, employed a tubulated retort, the tubu- 
lure of which was closed with a cork. When the salt had 
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