The Sun.
London, England, 1841-02-15 00:00:00

The water, inclosed in a long coil of small pipe (cem-
manly only half or three-quarters of an inch inside) is
passed through a fire of great intensity, which would
convert it into steam immediately, if the pressure on
the pipes was not great. But the pressure is very
great ; the pipes, including what is called the " expan-
sion pipe," are entirely tilled with water ; every orifice
is firmly closed ; and not the slightest room is left for
the expansion consequent upon the conversion of water
into steam. Under these circumstances, we have only
to urge the fire to a sufficient extent, and one of two
results must happen—either the pipes must burst, or
the water which circulates through them must be raised
to a temperature quite sufficient to account for any of
the circumstances which we have been describing. In-
deed, we do not see why the coil within the furnace,
the water passing through it, and the series of pipes to
some distance beyond it, may not be all made red-hot,
just as if the circulating fluid was melted iron or copper.
If this is a correct view of the matter, it follows that
the hot-water apparatus, as at present generally con-
structed, is exceedingly dangerous to the buildings in
which it is placed. The pipe. being almost universally
placed in contact with wooden floors and skirting
boards, and with a variety of combustible matters, the
only security for the premises is to be found in the cau-
tion of the party who attends to the fire, and who, by
any casual negligence, may cause a destructive confla-
gration. This brings us to the consideration of the se-
cond point—namely, how far the danger at present
existing may be obviated by a change in the apparatus ;
and we think there are two processcs by which this may
be effected. The better and more certain of these
(hut we fear not generally applicable to the hot-water
apparatus with small pipes, which is in most gsneral use),
would be to have a communication with the atmos-
phere (or, at all events, an orifice closed only by a plug
like the stopper of a bottle) at the upper end of the
expansion pipe. In that case the water could not
easily be heated much beyond 212 degrees ; because
any considerable pressure, either of water or of the
steam which would be generated, would drive out the
plug, and show that the fire had been urged beyond
the proper point. We fear, however, that a tempera-
ture of from 212 to 220 degrees, in a series of such
small pipes as are generally used, would not commu-
nicate sufficient warmth ; and therefore some other
mode of obviating the danger must be resorted to.
One plan which may be worth consideration would be
to form part of -the ascending pipe near the furnace of
lead, or of some alloy of lead and other metals, melting
at a temperature below that which would ignite wood ;
and then if the fire shoUld be urged too far, and the
temperature of the water raised too high, the leaden or
other safety pipe would be melted, and the only incon-
venience sustained would be the emptying of the pipes.
Lead itself melts at 6)2 degrees, which temperature,
we believe, wood will bear without material injury or
danger ; but, if it should be thought dangerous to allow
the pipes to be heated to that point, any of the alloys
of lead and tin, which melt at a lower temperature,
might be substituted. No doubt some difficulty would
be experienced in making the joints, owing to the
different rates of expansion of these metals and of iron ;
but that difficulty would probably not be very serious.
We are exceedingly glad to learn, that the Directors
of the Manchester Insurance Company, whose atten-
tion 'has been forcibly called to this subject by recent
occurrences, and whose interests are so deeply involved
in it, have appointed a Committee of their number to
make inquiries and experiments, with the view of ascer-
taining the real causes of the late accidents, and the
best mode of guarding against them.—Manchester
Guardian.

COLONIZATION OF AFRICA.

TO THE EDITOR OF THE SUN.

Stn,---Hiving noticed the letter in your Journal of
this evening signed " Joseph Soul," in which the writer
gives an account of the progress of the recent discussions
at the Egyptian Hall, on the subject of the colonization
of Africa by the free negroes of the United States, I
beg permission to make a most opposite statement to
that of Mr. Soul.

Without having the pleasure of knowing either the
Rev. Mr. Gurley or Mr. Scoble, but because I have
taken an interest in this discussion—believing that the
system of colonization established at Liberia is that
which alone promises to be of the slightest utility in the
real business of the suppression of the slave trade, I
have attended these meetings very regularly, and can
state distinctly that the departure of Mr. Scoble from
the meeting on the night mentioned by Mr. Soul was
under widely different circumstances to those described.
Mr. Scoble was heard very fully, and considerably be-
yond the time which it appeared afterwards had been
pre-arranged by the principals in the dispute—receiving,
moreover, very loud applause at the conclusion of a
powerfully worded, and energetically delivered speech.
But in the course of this speech Mr. Scoble had charged
the founders of the African Colonization Society with
" blasphemy—practical blasphemy"—and this the gen•
tleman attempted to prove by quotations from the
speeches of Mr. Clay-and other supporters of the insti-
tution, but in which quotations his opponent, Mr. Gur-
ley, showed afterwards that he had most grossly misre-
presented the real sentiments of the speakers—in one
instance having stopped short in the middle cf a sen-
tence, the conclusion of which, as given by Mr. Gurley,
reversed entirely the meaning of the speaker, and pro-
duced on the meeting an effect very little favourable in-
deed to the respect and confidence which the public
have-been accustomed to award to the principal speakers
at Exeter Hall. That Mr. Scoble was most disgrace-
fully overthrown by Mr. Gurley, and that his retreat
from the room was in reality occasioned by the exposure
to which he had subjected himself, was the opinion of
the whole meeting, excepting of a few persons who re-
tired at the same time, after hootings of a disgraceful
description—these persons being said (though how truly
I know not) to be the agents of the Anti-Slavery Society
at Exeter Hall.

Permit me to say, Mr. Editor, that few things have
been more unaccountable to many respectable persons
than the opposition of the Anti-Slayery Society to Mr.
Gurley—a gentleman whose mission to England might
have reasonably entitled him to a fair and courteous
hearing, at least, of all who are really solicitous of abo-
lishing the slave trade.
I am, Sir, your most obedient humble servant,
23, Crosby Hall Chambers, shopsgate-street,
Feb. 12th, 1841.