On Spontaneous Inflammations . 24# 
5. The Accumulation of Animal and Vegetable Substan- 
ces covered with Oil . 
If animal and vegetable substances heaped up in a 
large mass can be inflamed in consequence of the heat 
produced by their decomposition, this accident is more to 
be apprehended when they are covered with oily matters? 
and especially a drying oil. 
Besides the accident which happened at the manufac- 
tory of Lagelbart, and of which my colleague Haussman 
has given an account, and the fire which took place in 
one of the finest manufactories at Sainte Marie aux-Mines, 
we have other instances of wool, stuff, and pieces of cloth 
which were not scoured taking fire in magazines when 
folded up, and even during the time of their conveyance 
from one place to another, when heaped upon each other*, 
This is principally to be apprehended when linseed oil 
is employed in the manufacturing of cloth, or any other 
oil drying of itself, or rendered drying by oxide of lead. 
In cloth manufactories, therefore, no oil but olive or 
rape oil ought to be employed for greasing wool. 
It sometimes happens that in boiling flowers and herbsr 
in oil, which is the case in several pharmaceutic opera- 
tions, these herbs, after being taken out and dried, inflame 
spontaneously : care, therefore, must be taken, when 
they are thrown aside, not to heap them up near other 
combustible bodies. 
We have several instances of ships having been burnt 
in port either by the spontaneous combustion of cordage 
heaped up and strongly covered with pitch, or of a mix- 
ture of boiling linseed oil and lamp black inclosed in a. 
bag. 
6. The Boiling of Oily Matters . 
In the preparation of some kinds of varnish, such as 
printers* ink, where in general linseed oil boiled to % 
