S26 Spontaneous Ignition of a Carboy of Aquafortis . 
other facts is it immediately connected ? Whatever men 
of science may determine on these points, one thing 
seems to be evident, that if spontaneous combustion can 
happen thus to bodies so little inflammable as leather, 
silk, and wool, that instances of its occurrence in bodies 
easier to bum are more frequent than is generally sup- 
posed. 
Ignition of a Carboy of Aquafortis .* 
Sir — -An extraordinary accident lately happened to 
my neighbour, Mr. Watts, chemist, in the Strand, which 
has excited the attention of several persons of his pro- 
fession. I am anxious your ingenious readers should 
know some particulars respecting it $ and if you will in- 
dulge me by inserting briefly an account of the affair, I 
shall feel obliged, as it might in future prevent a more se- 
rious evil. 
Wr. Watts had taken into his premises, as usual, a 
carboy of aquafortis, and from some unknown cause, the 
following morning, his warehouse appeared to be on 
Are ; there being a great quantity of smoke seen issuing 
from many parts of the building. On entering the apart- 
ment, the carboy was on fire, and more than half con- 
sumed. I saw the remains of the basket and straw ta- 
ken into the yard. The air quickly revived the fire, and 
I have no doubt but 1 could very easily have blown it in- 
to a flame. Particular inquiry was made respecting the 
straw, and it appears to have been perfectly clean and 
new. There was no turpentine, or other inflammable 
spirits, within a foot of the spot where the carboy stood ; 
and it has very much surprised all who have seen it, 
how the acid could ignite such materials without the aid 
of other agents. Perhaps some of your scientific cor- 
* Tilloch, vol. 36. p. 234, 
