355 
Steam Engine, 
boiler^ but it may undoubtedly be applied to other pur- 
poses. Having shewn it to M. Auziliy, son of a consi- 
derable soap manufacturer of Marseilles, he thought that 
it might be employed with advantage in the making of 
soap ; and from what he told me of the process, and of 
the boilers employed in that art, 1 am persuaded that the 
experiment would succeed perfectly. 
But after all, it remains to be determined, whether it 
would not be still more advantageous to employ steam as 
a vehicle of heat in the making of soap, instead of light- 
ing the fire under the bottom of the vessel in which the 
soap is made. 
The result of an experiment which we are to make, M. 
Auziliy and myself, will probably throw some light upon 
this question.— 17 A’^icholsoji* s Journal^ p, 5. 
The boiler recommended by Count Rumford is by no 
means a new contrivance. Mr. Stevens obtained a patent 
in 1805 (the specification of which may be seen in the 
Repertory of Arts, Vol. vii. p. 173.) for a boiler formed in 
a similar manner, by a number of tubes placed parallel to 
each other, and communicating with a fiat vessel at one of 
their extremities ; the number of the tubes to be used 
was not defined by Mr. Stevens, and the capacity of the 
vessel that received the ends was much less than that here 
described, and though this must occasion some difference 
of external appearance, the principle is undoubtedly the 
same in both. 
There is no account of comparative experiments made 
with this new boiler and others, to enable us to decide on 
its merit. But as far as can be judged from a knowledge 
of various otlier experiments on boilers, we cannot have 
any good expectations of this form for boilers. The great 
additional workmanship necessary for it, must add consi- 
derably to the expence ; and the very remark which the 
