1842.] 



THE CIVIL ENGINEER AND ARCHITECTS JOURNAL. 



201 



The diminution of the bulk of the trenails, by the process, is from 100 to 

 63, and of the wedges from 100 to 80. It is found that the wood does not 

 swell until it is placed in a damp situation, as in the sleepers. Even the 

 most solid woods, such as African teak, can be compressed without sustaining 

 injury. Perfectly seasoned timber will not shrink after compression, but 

 green wood will shrink after the process. One of the principal advantages 

 of the compressed trenails is the firmness with which they hold into the 

 sleeper. Around the iron spikes generally used, a sheath of rust is formed 

 by the damp sleeper; the shaking of the carriages tends to draw them up- 

 wards, and the elasticity of the fibre around the hole in the sleeper being 

 impaired, it is of no use to drive them down again in the same place, and the 

 chairs eventually become loose. 



The mode of casting the chairs was described to be by placing an iron 

 plate on each side of the pattern, ramming them up in sand, and using an 

 iron core, which being sustained in its position by a projecting tongue falling 

 into a groove in the side plates, preserves an uniform incUnation of the rail 

 in the chairs. Extraordinary precision is thus obtained, and only about 2 

 per cent, of waste-castings are made, although they are subjected to a rigid 

 test, for if the bearing points allow the rail to vary -^ of an inch from the 

 required inclination, they are broken up. The iron cores do not unduly chill 

 the metal, and the average strength is retained. The iron used is chiefly 

 " Welsh Cold Blast." 



Mr. Cubitt's object has been to lay a railway entirely upon transverse 

 sleepers, of such a form as would expose the largest amount of bearing sur- 

 face for the least portion ot timber ; that the bulk of the ballast should be 

 beneath the bottom of the sleeper, where alone it is useful ; to use only the 

 best foreign timber; to have the rails rolled uniformly and sufficiently heavy; 



Rails, Chairs, and Sleepers, w ith the " Cramp Gauge " fixed. 



Guide Tube and Auger. 



the chairs simple in form, possessing great regularity, and giving the inward 

 inclination to the rail within the chairs, instead of depending upon the rail- 

 layer doing it in fixing them ; and that the fastenings should be simple, but 

 firm, and not liable to breakage, or to be detached by the passage of the 

 carriages. 



With these views he had directed four sleepers to be cut diagonally out of 

 each square log of foreign timber, giving about 2 J cubic feet to each sleeper ; 

 to place them with the right angle downwards, so that the ballast could 

 always be consolidated by ramming, without lifting the sleeper, or digging 

 around it, as with square, or other formed sleepers ; two places are planed to 

 receive the chairs, and one fastening hole bored in each sleeper ; they are 

 then kyanized in close tanks, completely filled with the prepared solution, 

 under a pressure of 80 lbs. per square inch. When placed upon the ballast, 

 the joint chairs are first put down 15 feet apart, and the intermediate chairs 



loosely placed 3 feet apart ; " cramp gauges," embracing the inside and out- 

 side of the rails, are then fixed between each pair of sleepers, and the wedges 

 along one side driven up — one trenail being driven in each chair, the hole 

 for which is previously bored in the sleeper by a gauge, to insure an equal 

 projection on each side of the rail. A " guide tube " of an internal diameter 

 to fit the spiral auger for boring the trenail holes, with the external lip 

 tapered to correspond with the hole in the chair for the head of the trenail, 

 is then used, and by its agency the holes are pierced with great accuracy, 

 concentric with the hole in the chair, at the same time protecting the tool 

 from being injured by the cast iron. The intermediate chairs are then fixed 

 in the same manner, and the operations are repeated for the opposite rails ; 

 the ballast is then consolidated by ramming. It is found that the work pro- 

 ceeds very rapidly ; the ballast supports the sleepers throughout, and has no 

 tendency to fall away from them ; the water drains away freely, and hitherto 

 the passage of the ballast wagons over that portion of the line which is laid 

 (although they are without springs), has been productive of benefit rather 

 than injury. 



The inclination of the rail being given in the chair had insured such accu- 

 racy, that after one day's traffic over it, the surface of the rails is rubl)ed 

 equally throughout, and not alternately on either side, as is so commonly the 

 case. 



Mr. Cubitt did not claim the invention of the angular-formed sleeper, as 

 Mr. Reynolds had used it before for his longitudinal bearing rails, but he 

 believed that transverse sleepers of that form had not been previously laid 

 down ; nor did he claim the compressed wedges and trenails, or the peculiar 

 mode of casting the chairs : the merit of these was entirely due to Messrs. 

 Ransome and May, who had entered completely into his views and wishes, 

 and executed them with extreme inteUigence. 



In answer to questions from the President, Mr. May replied that it had 

 been an object to gain in the trenails and wedges the greatest amount of 

 strength with diminished bulk, and also to cut away as little of the sleeper 

 as possible in boring the holes ; he had, therefore, introduced this method of 

 compressing them, with a view also, that in swelling from the damp they 

 should fix themselves tight into the soft timber sleeper, and hold the chair 

 fast down. 



He hoped to extend the use of compressed trenails to ship-building, for 

 which they were eminently adapted ; if they were used, smaller holes would 

 be bored in the timbers, and they would hold tighter than the trenails now 

 used, which reqnire to have the points split and wedged up. and the heads 

 also divided and caulked to prevent leakage through the open sap vessels of 

 the wood. 



The President remarked that on the Hull and Selby Railway, the chairs 

 were fastened to the kyanized timber sleepers by uncompressed wooden 

 trenails. 



Mr. Cubitt was not aware of that fact ; he had always found that uncom- 

 pressed wedges and trenails would not hold tight. Some of the compressed 

 trenails had been wetted by accident, and could not be afterwards driven into 

 the holes in the chairs ; they nearly resumed their original size, and then 

 showed the marks of the turning tool upon their surfaces. In answer to a 

 question from Mr. Parkes as to the comparative expense of laying the line, 

 it was rather in favour of the system he had adopted, although the prices 

 paid for the items separately, were higher than usual, but the saving in 

 labour, and the almost total absence of waste of materials, gave the economy. 



He then quoted a few of the prices paid ; sleepers 6s. 6d. each (ready to 

 lay down, including kyanizing) ; chairs 9/. per ton, free from faults in casting, 

 the contractors for them replacing all that were broken in laying the line. 

 Each joint chair, with three trenails and one wedge, 2s. lOd. Intermediate 

 chairs, with two trenails and one wedge, 2s. Id. each. The labour for laying 

 the line was from 2s. to 3». per yard running ; the cost of fixing the sleepers, 

 laying the rails, and ballasting complete, was from £1500 to £2000 per mile, 

 including allexpences. 



Mr. Macneill fully concurred in the importance of providing for clear 

 drainage from the sleepers ; and in the advantage presented by the angular 

 form for ramming the ballast. The transverse sleepers, with such rails as 

 had been used on the South-Eastem Railway, were preferable to a continuous 

 bearing, as (hey would prevent the gauge from widening, and preserve an 

 uniform regularity of surface, which would tend materially to diminish the 

 oscillating motion so common on railways, and which was so destructive to 

 the engine and the carriages ; altogether this railway appeared to be the 

 most perfect he had hitherto seen. 



He was using, on the Dublin and Drogheda Railway, chairs of somewhat 

 similar construction, with uncompressed wooden wedges and fastenings ; they 

 were very roughly cast in Scotland, with hot-blast iron, and the breakage 

 was very great ; they, however, cost less than 5/. per ton. He believed that 

 chairs such as were cast by Ransome and May would be cheaper at 9^ per 

 ton. The uncompressed trenails were found in many instances to become 

 loose. In ballasting the railway, as stone was cheap, the whole surface of 

 the line was pitched transversely with thin stones, and then a good bed of 

 broken stone used for ballast, in the same manner as Mr. Telford bad pro- 

 ceeded with the Holyhead Road. 



Mr. William Cubitt had compressed a considerable quantity of wood wedges, 

 by forcing them singly, by the blow of a piston, through a taper steel mould ; 

 on leaving the mould they had attained their ultimate state of compression, 

 and they were some time before they reassumed their original bulk, but he 

 conceived that Mr. May's plan, by which they were dried in a compressed 

 state, enabled tbem to retain their form longer. He considered the systems, 



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