The Sun.
London, England, 1850-03-25 00:00:00

CRIMINAL RETURNS.

Mr. STANFORD wished to ask the Secretary of
State for the Home Department, whether instructions
to the statistical department of the Board of Trade
might not be given so as to insure more eomplete crimi-
nal returns for the United Kingdom.
Mr. LABOUCHERE admitted that the returns did
not contain all the information the public ought to have
on the subject, but the question of extending the returns
was now under consideration.
THE GOLD COAST.

Mr. COBDEN understood that the extension of Bri-
tish territories on the Gold Coast of Africa had been
recently negotiated, and he wished to know whether an
opportunity would be afforded the House of discussing
the policy of that extension of territory.
Lord JOHN RUSSELL was understood to say that
a vote would be taken to complete the purchase, and
then a discussion might be taken.on its policy.
Mr. COBDEN gave notice that he should take the
sense of the House after Easter as to the policy of pur-
chasing the torts at all.
DUCHIES OF CORNWALL AND LANCASTER.
Mr. TRELAWNY rose to move for a Committee to
inquire to what extent the public are entitled to claim
an interest, present or prospective, • in the
management of the Duchies of Cornwall and Lan-
caeter, with respect to which returns aro annually
made to this Home, and, with regard to the Duchy
of Cornwall in particular, to inquire where
its accumulations are invested; who is the heir of per-
sonal estate to the Prince of Wales; whether Duchy
dues from mines are reserved in minerals or money, and
whether they are rated to the poor; whether mines are
directly worked by the Duchy officers ; what
number of claims to estates have been made
and not sustained during the last six years; whether
there is any good reason for the direct exception of
certain kinds of property in the Duchy Act of 1844
(such as royalties, francises, and estuaries), from the sta-
tutory provision for the quiet of titles, now applied to
Crown property, to private property, and most descrip-
tions of Duchy property ; and, lastly, whether the manage-
ment of the Duchy estate has been satisfactory as
tn. The
topn. %ro
Membere at ent in
r
regards the public, fair as regards its•own tenants, or pro-
ductivei the
o e state
tt f show
the
r rural
a a lP°Pu
seriesa .
o
of figures, that the txpenses of management eat up the
whole of the property.

(LEFT SPEARING.)

INSTITUTION OF C IVI C ENGINEERS.
On Tuesday, March 19, William Cubitt, Esq.
President, in the chair, the discussion on Mr. W.
Fairbairn's paper, "On Tabular Girder Bridges,"
was renewed, and continued through the evening.
The subject was resumed at the point where it was
left on the last discussion of March 12th; and Messrs.
Wild, Pole, Rennie, Scott Russell, Eaton Hodgkinson,
Walker, Glynn, dder, Professor Willis, General
Pasley, and Captain Simmons, R.E., examined the
question at great length, arid under all views, illus-
trating their position by diagrams and models used
in the experiments and in the mathematical inves•
tigation.

It was stated, that after the remarks made at the
last meeting, it was merely requisite to describe the
experiments alluded and before doing so, to briefly
describe their object.
In the report of the G,Ararnment Inspector, the
limiting strain required for the public safety was de •
fined, and the Torksey-bridge had. bean condemned
for not complying with those conditions. A. calcula-
tion, therefore, had been made to ascertain the actual
strain on the bridge. It appeared, however, that it
was really less than the limit prescribed by the Govern-
ment Inspector. The experiments instituted were fa-
the purpose of testing these contrary results. It was
also stated, that in the paper there were many
objectionable points, but particularly one that was
positively dangerous.
The author had not only omitted the effect of the
continuity cf the Torksey girders, but stated that it
was safer to do so. Now all writers upon the sub-
ject, and all who had considered the matter, agreed
that in a continuous beam the effect of continuity was
most important, and that in a perfectly continuous
beam, the strain over the supports was even greater
than elsewhere. It was there fore submitted that this
was not the part, the consideration of which it could
he " safer to omit."

The form taken by a continuous beam, when uni-
formly loaded, was convex over the supports, and
concave between the points at which the convexity
ended ; at these points of contrary flexure, the hori-
zontal strains were null, and the beam might then
be severed, without altering its condition. The
virtual length of the beam, in the Torksey Bridge
was determined by the distance between the exterior
support and the point of contrary flexure ; and it was
to determine this point practically that the experi-
ments were instituted. It was shown that this point
was 214 feet from the centre support, and that hence
the length of the beam was reduced from 130 feet
to 1681 feet.
The compressive strain upon a girder of this length,
loaded as prescribed, was 44 tons per inch, being
less than the limit defined. Consequently, it was
asserted that the railway company to whom this bridge
belonged had been deprived of its use, not in conse-
quence of any omission on the part of their engineer,
but in consequence of the inability of the Govern-
ment authorities to appreciate the strength that had
been provided.

•
In reference to the application of formulm to the
calculation cf the strength of the girders, it was con-
sidered desirable, in such an important case, not
merely to form a general approximate notion f the
strength of the bridge, but to ascertain, with all
possible exactness, the nature and amount of the
strains to which the structure was exposed ; and this
could only be done by using a comprehensive process
of calculation, which should embrace all the elements
affecting the strength of the bridge.
The effect of the continuity of the girders over the
two openings, was carefully considered, anti the
nature of its effect upon the strain was explained, as
deduced from the application of the most modern
mathematical investigations, and it was demonstrated
that the strength of the beam was thereby augmented
above one-third.

It was then shown, how the rules for estimating
the strength of elastic beams, were rendered applic-
able to the case of the Torksey bridge, and the results
proved that when the bridge was weighted with the
load prescribed by the Government authorities as a
test for its strength, the strains of compression and
extension were only one-half of what competent autho-
rities had stated might be safely applied.

The diagrams exhibited shoWed the results of ma-
thematical calculation, as applied to the Torksey-
bridge girders, and the remarkable coincidence of
these, with experimental results obtained by other
investigators in an entirely different manner, was
insisted on, as a proof of the correctness of the con-
clusions arrived at.

It was sta►ed, in reply to a remark upon the in•
creased deflection due to velocity, that the result of
the experiments tried by the " Cast-Iron Bridge
Commission," proved that " this increase was wholly
insignificant in beams of the length and stiffness of
those of the Torksey•bridge.
The discussion was summed up by its being stated,
that, with one exception, all those who had spoken
during both evenings, agreed that the formula given
in the paper was empirical and not trustworthy ; that
the effects of percussion and increased velocity were
practically only shadowy visions ; and as it was ad-
mitted, that in the calculations of the Government
Inspector, the effect of continuity was neglected, and
as it had been proved, that the strain was less on the
bridge than that assigned as requisite for the public
safety, and that it was, in fact, amply strong, it was
evident, that the public had been wrongfully de-
prived of the use of this bridge, and the company had
been prohibited from gaining the just return for the
capital invested, in consequence of an incomplete
investigation, and the assumption of untenable formulme.
The papers announced to be read at the meeting of
Tuesday, March 26th, were " Description of the
Chapple Viaduct, on the Colchester and Stour Valley
Extension of the Eastern Counties Railway," by Mr.
Peter Bruff; Assoc. Inst. C. E., and " On the Ma-
nufacture of Iron, with Experiments on the Strength
of Railway Axles," by Mr. G. B. Thorneycroft,
Assoc. Inst. C. E.

RESPITE. The sentence of death passed upon
Sansome, the man convicted at Nottingham assizes fbr
murder, through procuring miscarriage, whore the girl,
Bailey, died, has been respited until the lit of May.
This implies that his life will be spared.
YARMOUTH, MARCH 23.—The sloop Ancholin, of and
from Boston to Maldon, got on the beach at llermsley
this morning, when the crew either left her or were
washed overboard; she soon after came off, and was
brought in hereby boatmen a derelict.

FIIIGUARD, MARCH 24.—1 t blew with exceeding
violence at N.N.E. yesterday morning.—The Margu-
retta, of Cardegan, beached on Goodwood Sands. The
Lily, from Milford, got i❑ contact with the Rev.
Theobald Mathew, and lost bulwarks and stanchions :
the latter received no damage.