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how much water they consumed, and how much fuel 
they burnt, but he could get no mformation, and yet Mr. 
Hartop would probably allow that if this object could be 
accomplished it would come very near to the test of how 
much of the extra duty performed was produced by 
the consumption of fuel, how much depended upon the 
difference in the boilers, and how much upon the difference 
in the arrangement of the machinery. Mr. Hartop had 
stated that the Cornish engines would raise half as much 
more steam, and that they would do three times the duty ; 
there was no reason to doubt that ; and supposing it to be 
true, it was apparent that if an increase of one-half in the 
steam would treble the work done, mnch of it must be set 
down to improvements in the machinery after the steam 
leaves the boiler. If the society should take up the inquiry 
which had been suggested, he hoped that the particulars to 
wliich he had alluded w ould be included in the inquiry. 
Mr. Hartop said that this point was one which had 
occupied the serious attention of the British Association 
for the Advancement of Science, and a sum of money had 
been voted for the purpose of making experiments on 
boilers in Cornwall and elsewhere. He would, however, 
beg to direct the attention of gentlemen to a very 
interesting paper published by the Society of Civil Engi- 
neers — a paper by Mr. Parker, on Steam Engine Boilers, 
which contained much valuable information on this im- 
portant subject. He (Mr. Hartop) had assigned a great 
deal of the saving effected by the Cornish engine to the 
improvement of the boiler, but Mr. West was correct in 
supposing that a great deal was to be attributed to the 
improvements in the machinery. In Cornwall, a great 
saving was effected by surrounding the boilers and cylinders 
with non-conducting substances, which conserved the heat 
so much that it was no uncommon thing for a Cornish 
engine-house to be so cold as to require the use of a great- 
coat, whereas in Yorkshire and other places they were 
generally at a very considerable heat. 
Mr. Embleton trusted that the meeting would see the 
importance of the question started by Mr. West, namely, how 
much water could be evaporated in a boiler of a given size, 
by a certain quantity of coal. This, he thought, was distinct 
from the improvements which had been effected in the 
Cornish engines, for though their power had been greatly 
increased by the better conservation and apphcation of the 
steam when generated, it did not necessarily follow that a 
greater quantity of water had been evaporated by a given 
quantity of fuel in the Cornish boiler than in the waggon 
