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TRANSACTIONS OF THE SECTIONS. 127 
tionably reduced, and thereby one-half the lineal weight saved, which compensated 
for the difference of price. The material point which supervened in favour of 
wrought iron, was that it gave ample warning by great deflection before the breaking 
point was reached, which was not the case with cast iron. 
By experiment it was found that with double T-iron, 8 inches deep, and the top 
and bottom flanges each 4 inches wide, the whole § inches thick, and having two 
girders 10 feet apart and 10 feet span, witha load of 21 tons, within a radius of 
4 feet from the centre, the deflection was only 2 inches, and immediately on the load 
being removed the beams returned back to their original position. Other examples 
were given for the Members to see at the Belfast Iron Works, the result showing 
that with the given section the depth ought to be about y5th the span, and the 
thickness of all parts 7;th the depth of girder, while the best form was for the flanges 
to be 3 the depth. 
The paper was accompanied by drawings showing the different points bearing upon 
the advantages of this new feature in the application of malleable iron, so interesting 
for security of life and property in fire-proof buildings. 
On an Improved Cast-Iron Sleeper for Railways. 
By Joun Gopwin, C.E., Belfast. 
Mr. Godwin said that his attention had been a good deal directed to the subject 
of laying and upholding the permanent way of railways, from the necessity which 
had arisen on the Ulster Railway with which he was connected, of relaying a con- 
siderable length on which the timber was decayed, and a large outlay became neces- 
sary for its reconstruction. ' 
The Ulster line is laid on longitudinal bearings of timber, and the rail is of the 
bridge-form, of about eighty pounds to the yard; although this kind of permanent way 
has answered exceedingly well, yet the certainty of decay in the timber, and the conse- 
quent necessity of frequent reconstruction, inflict a serious outlay on the company, 
and renders a large reserve fund necessary to meet such contingences. 
In the hope of obviating this serious and frequent source of expense, he directed 
his attention to the cast-iron sleeper for the bridge rail introduced by Mr. Barlow, 
and patented by him; on examining the lines on which this sleeper had been laid, 
he thought that an improved mode of fastening the rail to the sleeper was required, 
and that the form of the sleeper itself was capable of some improvement. 
In Mr. Barlow’s plan the sleeper is flat, and the rail is secured to it by means of 
small detached pieces of iron and small screw bolts; these bolts are liable to shake 
loose, and the stability of the line is consequently injured. 
The alteration which he (Mr. Godwin) had adopted in the form of the sleeper is 
in making it curved instead of flat, and thus giving it more strength, a better hold 
on the ballasting, and effecting a consequent saving in the labour of packing and 
adjusting. ‘ 
In Mr. Godwin’s plan, the chair on which the rail rests is so constructed as to 
project over the flange of the rail on both sides, and is secured by a broad wedge 
driven between it and the under side of the rail, forcing it upwards against the pro- 
jections of the chair: the joints are fastened in a similar manner by a single wedge at 
each joint. 
Betore Mr. Godwin had tested this plan of permanent way, by laying a length of 
it and subjecting it toa severe test, he was apprehensive that the wedges would 
shake loose, and that it would not remedy the defect of the screw fastenings; but after 
a severe trial of six months he found the line as secure as when first laid, although it 
had not been packed or otherwise meddled with; he found, however, that a few of 
the joint sleepers had broken, but without in the slightest degree affecting the per- 
manence and steadiness of the line. 
In order to prevent a recurrence of this he has determined on laying the joint 
sleeper transversely, and thus preventing the possibility of their breaking. 
The advantages to be expected from this kind of permanent way, are its durability, 
simplicity of construction, facility of replacing defective rails, and ceconomy in up- 
holding. 
