Star.
London, England, 1817-08-18 00:00:00

REPORT °fare COMMITTEE on STEAM-BONS.

(Concluded from the STAR of Wedoesesday.)
Mr. 1 hamar Lean called in, and e:: :mined.
'Will you si ate %cur profession. and place of abode?
—I reside at Crowan in Cornwall, and I am employ.
ed by nearly the wh,,le of the miners in Coma all to
inspect their engines, and make monthly reports of
the work they perform.
You are then well acquainted with steam engines
of every various construction ?—Certainly I am; I
see fifty-seven every month
Do you conceive that there is any material diffe-
rence in the vaoective safety of those engines?—
Some of the eligines are certainly safer than others.
Be so good us to state which, and why ?—I con-
ceive there is Li a dinger whatever in the use of high
pressure steam engines; and for this reason, that in
general, for an engine that is interacted to be worked
with high steam, the materials are made stronger in
proportion than the materials used for steam of low
pressure.
What are the precautions which you think it neces-
sary to take, in order to render a high steam engine
perfectly sale from accident ?—The rn demi, should
be made strong enough, and there is no difficulty in
doing that ; and there is a good deal depending en
the construction of the safety-valve, which should be
so constructed as to go quite easy and without any
possibility oi sticking. •
Do you nut o:ink it of importance, it not reces.
nary, that a boil-r should have two safety-valves ?---
Certainly ; and every high Rome steam engine that
if attend to has two safety valves.
Do not you confine one of those from the engine
man?—Not in any instance.
Should you or not think it necessary, on board a
boat for passengers worked by a steam engine, that
there should be an additional safety-valve to the
boilers which the engine-man could not come at to
prevent its operation ?—That-would certainly be very
desirable, and I should think necessary.
Have you any choice, in point of safety only, be-
tween a boiler constructed of cast iron or of wrought
iron ?—Were I to baye a boiler where I wished to
have the greatest strength, I would certainly have it
made of cast iron ; 1 have not one doubt that a cast
iron boiler can be made much stronger than it is pos-
sible to make a wrought iron one; in fact the explo-
skins that we have had in Cornwall have all been in
wrought iron boilers, but I never had one in cast iron
boilers, nor have we had an accident from high pres-
sure steam ; all the accidents have been from low
pressure steam in Cornwall.
To what do you attribute that ?—I attribute that
to the boilers not having their proportionate strength
to the weight they ought to bear, that the high pres-
sure steam engines have.
Of what nature are those failures which usually
happened in the wrought iron boilers?—The one
which I witnessed the explosion of, threw off the man-
Is le door.
Do you mean that the bolts by which the man-hole
dour was secured gave way ?—Yes.
Are there not man-holes to cast iron boilers ?—Yes.
Then might not the best constructed and the
strongest cast iron boilers have been equally liable to
the accident you have been mentioning, from the mere
failure of the bolts, by which the man-hole door was
secured ?—Certainly not, and for this reason, the
man-hole door to a cast iron boiler is contrived to be
flu the inside; it dues not depend upon bolts at all as
they a:e constructed with us, it bears against the side
Of the boiler.
Would it not be equally easy to affix man-holes so
constructed to wrought iron boilers?--There is no
difficulty in doing it, either one way or the other.
Supposing a cast iron boiler and a wrought iron
boiler to be exploded by having too great a pressure
applied, from which of the explosions should you ap-
prehend the great-cc danger ?—I think the danger is
equal from one as the other.
In what manner do you apprehend then, that a cast
iron boiler would explode ?—Probably there might be
some parts of the cast iron boiler separate, and the
wrought iron boiler would probably rend.
Shettl.l rot not then apprehend a greater danger
from the explosion of a boiler which burst into frag-
ments, than from one which only rent ?—ln every
boiler that is built, there is one part of it weaker than
another, and it is hardly possible for a boiler to. be
thrown about in fragments to do mischief. 1 shohld
not feel any hesitation to sit on the cast iron boilers I
base seen in Cornwall when an explosion took place ;
I am convinced the explosion would take place at the
under part.
Do you think it necessary or advantageous that
those boaers should be proved at their first erection,
rind that that proof should afterward; be repeated at
intervals ?—li is certainly desirable it should be done
at the first erection ; they ought always to be proved;
the cast iron boilers which have come tinder my no-
tice in Corn Wall, I calculate to be sufficient to resist
at least thirteen times the pressure of steam we have
ever used in them,
To what heat are those boilers usually proved ?
We work in general 40 lbs. to an inch in the high
pressure boilers, and we prove them sometimes as
high as three hundred.
By a proof of this nature, so much within the sop-
poted capacity of resistance of a boiler, pp do not
apprehend that any risk is incurred of injuring it ?
Certainly not.
And you yet conceive, that the proof is so far be.
yond the ordinary resistance which is required from,
the boiler, as that there is no danger whatever of its
bursting with a pressure of 40 or 5() lbs. an inch,
when it has been proved by a pressure of three hun-
dred ?—Certainty not.
,Do you apprehend, that it is perfectly easy so to
construct and to secure your safety.valves, as that no
engine.man, however careless, shall be able to raise 11
the steam beyond the pressure of 40 or 50 lbs. per
inch ?—Thele certainly is not the least difficulty in it.
You apprehend then, that with a boiler so con-
strticted, so proved, and so guarded against careless.
mess, there would be no danger whatever in any situa-
tion t.-Certainly not.; neither in a steam boat or an
engine employed In a manufactory or mines, or in
any manner whatever.
As 'to the economy in the use of coals, what is your
opinion ?—My opinion is, that the high pressure en-
gines in Cornwall have saved at least two-fifths of
the who!e consumption of coals in the county; in
some instances it has saved three•fifths.
What means bare you for ascertaining that fact ?

In the mimeo of my ordinary employment,
attend to the various engines in Cornwall, and com
pute their duty; the quantity of coals that is con-
sumed by the engines, is rendered to me an oath ; it
is the same that is sworn to at the Custom-house.—
The ascertaining the weights which the engine lifts
is caretolly and correctly measured ; and from this I
calculate the work performed by the engines, of
which I make a monthly report, and find, that tlicse
engines which work with a high pressure steam are
more economical in their operations than those c: the
low pressure, so much so, that were the low pres-
sure steam engines to be introduced into the mines
of Cornwall, it would stop upwards of two-thirds
of them. _ _

Is the paper which you have, one of those accounts ?
It is the account for thelast month.
And this account you have declared, upon your
own knowledge, to be accurate as to the particulars
it contains ?—I do.

Do you consider it as important to the safety of an
engine, that the boiler should be frequently cleai.sed ?
It a boiler is foul, if there is a quantity of mud in it,
it may prevent the water from coming in contact
wits the iron, and in that case the boiler is liable to
injury; 1 have known a wrought iron boiler to burst
from that very cause; I never knew a cast iron boiler
to explode in any instance.
Is there any difficulty in subjecting the boiler to
the usual proof, every time it is cleansed ?—There
is no difficulty whatever, any other than having the
apparatus prepartd for it, which is very easily done.
Is that apparatus chinr expensive, or difficult of
construction or application ?—No.
Can it ►.e applied with ease by any engineman or
engine proprietor, who is at all acquainted with the
construction or working of a steam engine ?—Y••s ;
and the mileage:trent of it is so plain that no persons
can misunderstand it, if they are acquainted with all
the other parts of the engine.
In what does this proof consist, and how is it per-
formed ?—The proof consists of first filling the boiler
with water, and then loading the safety valve to any
point required; then injecting water by a forcir v.
pump, till the safety valve, with the additional weigh;
upon it, is raised.
Have you any other suggestions to make on the
subject of the setety of steam engines, besides what
you have already said ?—I think not.
Mr. George Dodd, again called in, and examined. .
For what purpose do you attend ?—To produce a
new safety valve.
What are the advantages attendant on the safety
valve which you have to offer to the Committee ?
I propose to the Committee the valve I now offer as
a second valve, as it admits of being locked up so
as to be inaccessible to the engine worker ; it prevents
the possibility of his obstructing its action, either by
going into the boiler when the boiler is cool, ot
under any circumstances whatever.—[The witness
produced it.]
Is there any provision against the valve adhering
in any part, so as to prevent its operation ?—There is;
the safety valve has not a conical bottom as is usual
in most safety valves, but has a flat bottom resting
upon a flat circular ring. the steam escapes from the
sides of the box thr'•ua:h apertures, so constructed as
that nothing can be introduced to impede its action.
Later, Eq. called in and examined.
What is your place of abode and profession ?—I
am an engineer, residing at No. 3, Mount-street,
Lambeth.
For what purpose do you attend ?—To exhibit the
plan of a safety valve, in consequence of my having
presented a Petition to the House of Commons, which
was referred to this Honourable Committee.

Be pleased to produce your plan ?—The valve of
which 1 here deliver in the drawing, is so constructed
as to prevent the pos►ibility of any person having
access to it to prevent its action ; it is self-acting en•
tirely from the gravity of a column of water acting
upon the valve, which prevents its being locked by
any mode, and it cannot adhere because it is not a
cone acting in another cone, but a fiat surface pres
sing upon the top of a cylinder and being enclosed
in a box and the steam getting out at the bottom,
there is no matter can get upon the valve to cause
;is adhestQn.

T!'e works of the Regent's Canal were resumed on
his Royal Highness's Birthday; the compittlon of
the tunnel under Islingtun being the first object, un-
til arranrements can be made for employing the un-
occupied poor along a space of more than six miles
in the diSerent parts and works of the Canal, from
the Hampstead-road to the basin at Limehouse.
Thursday se'nnight Lord Bec-rtvz, accompanied
by numbers of the Nobility and Gentry, assembled
at the Trim Assizes, laid the fitst stone of the very
beautiful Corinthian Pillar, now .2recting there in ho-
nour of the Duke of WELLINGTON. His Lordship
nude a very animated and appropliate speech on the
occasion, and paid a just tribute to the character of
the illustrious Hero, which was highly gratifying to
the assemblage, who gave three most hearty cheers.
Wednesday, as a man of wars boat Was bringing
into Margate a contraband boar, with a cargo of
105 tubs of liquor, and tour smugglers belonging to
it, a large concourse of people assembled on the
Pier-head, and when the boat approached the shore,
assailed the midshipman and his crew with such a
shower of brick-bats and stones, that they were
forced to give up the smugglers, who made their
escape.
At Deddington. near Oxford, one day last week,
a little pig having got its head between two rails, and
crying out vehemently, a boy ran to its asti.:ance,
and while in the act of extricating it, the sow, its
mother, seized him by the arm, broke it in two
places, and terribly bruised and lacerated it with her
teeth. _ _

ATROCIOUS MURDER.—An atrocious murder was
discovered, near Petersfield, on Thursday mousing
last t the unfortunate victim is supposed to hive betn
in the habit of travelling the country with crockery-
ware. His body was discovered about ten o'clock in
the morning, in a hay field, close adjoining the turn-
pike road, within a quarter of a mile of Petersfield ;
his breeches, or pantaloons, and hat, were missing ;
the body, which had several mortal stabs about it, did
not appear to have lain long in this state ; on his
shirt was masked "Z. Searsun, No. 7, 1811." The
perpetrator of this foul and apparently cool-blooded
act, is supposed to be a sailor, with whom the de-
ceased was seen in company, OR the previous after-
aeon and evening.