300 = Of securing houses and their inhabitants from fire, 
volume of the Philosophical Transactions; having had neither time 
nor opportunity for the purpose. But I may remark in general, as 
to what has been stated, that such is Lord Mahon’s character, for ve- 
racity, sagacity, perseverance and precision, that his account may 
be thoroughly depended upon; farther sanctioned, as it is, by the 
tacit assent given to his statements by Sir John Pringle, then Presi- 
dent ofthe Royal Society, and by the necessary inquiries of the 
Committee of Publications, of that respectable body on this subject. 
As his Lordship tells us, (p. 891,) that he had made “a prodigious 
number of experiments upon every part of his methods,” it is unfor- 
tunate that we are not furnished with his theory on the subject: in 
question, in his own words; since the extensive course of experi- 
ments in which he was engaged, must have furnished him with many 
hints, which he had an opportunity either of confirming or of rejecting. 
We now proceed to Mr. D. Hartley, who] may here add, was 
son of the celebrated metaphysician, Dr. Hartley, and a person not 
wanting either in correctness or enthusiasm. His methods however 
on the subject here in question, must be considered as amounting to 
little more than a variation of those exhibited by Lord Mahon; who 
tells us in the title to his memoir, that he had invented the plan; 
which assertion, he twice confirms in the body of his memoir; and 
I have no recollection, of any counter claims, having occurred on 
this occasion. | 
Mr. Hartley operated upon a brick building, apparently well put 
together, and having at least two stories. It was situated on a com- 
mon, near London ; and the experiment was tried in the presence of 
a large assemblage of persons, among whom were many of high sta- 
tion and character. ‘The registers of the day, doubtless give the de- 
tails of Mr. Hartley’s. proceedings, and J myself can vouch for the 
following fact; namely, that any person riding past, some short time 
afterwards, could (from without,) discover no other injury done. to 
the building by the opération which it had undergone, than that the 
brick-work above one or more of the windows, bore strong marks 
of the action of a fierce flame upon it; this flame appearing evident- 
ly to have issued from within the building. 
We now take leave of these spirited’ and respectable sveiedetis 
ers, by saying, that we must not wonder after all their labors, that 
the good people of England, have not generally profited by what 
was thus twice brought under the view of their metropolis. This 
indifference, has been owing partly, to the difficulty of changing na- 
