Intelligence and Miscellanies. 187 
10. Explosion of oxigen and Phosphuretted hydrogen. 
The violent action of phosphuretted hydrogen and oxi- 
gen, of course, induces every demonstrator to be extremely 
cautious in bringing them together. Like others, I have 
been accustomed to permit a succession of single bubbles 
of phosphuretted hydrogen, to rise through a column of wa- 
ter, into a few cubic inches of oxigen gas, in the upper part 
of a bell glass, and thus to exhibit the splendid flashes of 
light, which are renewed at every contact of the gases. In 
some former years, explosions, attended, however, with no 
other injury than the breaking of the vessel, have result- 
ed from the fact that, occasionally, a few bubbles of 
gas, probably less charged with phosphorus than others, 
ave broken in the oxigen gas without exploding, thus pro- 
ducing, however, an explosive mixture, which a succeeding 
bubble, more highly charged with phosphorus, has kindled, 
and thus caused the whole to detonate. bs . 
_ Ata recent lecture, the usual arrangement being estab- 
lished, a single bubble of phosphuretted hydrogen passed up 
into the oxigen, and, as I was afterwards informed by 
an observer, remained unbroken. The mouth of the 
retort was plunged not more than an inch and a half be- 
neath the surface of the water, and this slight hydrostatic 
pressure, giving a little condensation to the gas, probably 
caused rather a larger volume of it than usual to pass into 
the oxigen, when the next bubble rose through the water. 
It is not probable that more than three common bubbles of 
the inflammable gas were mingled with as many cubic inches 
of oxigen gas, when a very bright flash of light, accompa- 
nied by an extremely violent detonation, ensued—shatter- 
ing all the glass vessels in the vicinity, and projecting frag- 
ments of the bell glass in every direction, among an audi- 
ence of three hundred persons, and to the extreme distance 
of forty feet, slightly wounding a large number of the spec- 
tators. 
So sudden, violent and unexpected a result from so tri- 
fling a cause, appears to me worthy of being mentioned, as 
an inducement to the most scrupulous caution in the man- 
agement of these violent agents. —Editor. 
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