356 
Steam Engine. 
Count makes on the advantage of numerous small boilers, 
with each a separate fire-place, shews that he was at least 
doubtful in recommending the use of this on a large scale. 
The Count has made a considerable mistake in assert- 
ing that an equal surface will have more strength to re- 
sist internal pressure in a boiler of the shape proposed than 
in one of the common form ; the sum of the pressure in 
all boilers, with the same force of steam, is demonstrably 
as their internal surfaces, and the only difference the form 
makes, is, that globular forms are least liable to have their 
shape altered by the pressure, flat forms most, and the in- 
termediate shapes more or less so, as they most resemble 
the flat or globular form. 
A variety of plans have been tried to make the same 
quantity of fuel produce greater effects by some particu- 
lar formation of the boiler ; among these, none seem su- 
perior to that for which Mr. Edmond Lloyd, in the Strand, 
obtained a patent, in simplicity or effect ; the principle 
has hitherto been used chiefly for kettles, and other small 
vessels made for sale by Mr. Lloyd ; but there is no cause 
why it should not do equally well for large boilers ; and 
there is reason to think that they would be much prefera- 
ble to the Count’s new boiler, and would certainly cost 
much less. 
One of the kettles of this form will boil two quarts of 
water in less than ten minutes, with less than a third of 
one of the common penny bundles of fire- wood, sold every 
where in London. As a description of the principle on 
which they are made may be acceptable, the following 
account of it is presented to our readers, to most ol whomj. 
we believe, it will be novel. 
