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THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[December, 



INSTITUTION OF MECHANICAL ENGINEERS. 



At a iiieotinir of the above Institution, held at Birminirham, 

 Nov. 2tth, R. Stepiiknso.v, Esq., M.l'., in the Cliair, the followinff 

 ])a])ere were read: — 



ON THE ECONOMY OF RAILWAY TRANSIT. 



On the Ernnnmii of RiiUimy Transit. By Mr. J.\1MES Sa.iivkl, of 

 the Eastern Counties Railway. 



TliC olijeot of the paper was to show the necessity of working 

 l)ranch lines with ligliter and less e.\pcnsive trains and locomotives 

 tlian are at present in use, with a view to diminish first cost, con- 

 sumption of coke, and deterioration of permanent way. My returns 

 of the number of passengers conveyed on the Eastern Counties 

 and Norfolk Railways, they showed that the greatest number of 

 passengers in any main line train at any one time was 231, and the 

 least number 7; the greatest number in any of the branch line 

 trains being 82, and the least number 3. And that there were con- 

 veyed on the Eastern Counties branch lines during the year 1847, 

 42,644' tons of passengers (calculating each passenger with his lug- 

 gage at 168 lb.), and that the weight of engines and carriages 

 required to convey them was about 1,112,500 tons, being in the 

 proportion of 2S to 1. 



The main line engines consumed from 24|^ to 40glb. of coke per 

 mile, and the engines for working the branch line trains consumed 

 from 16^ to 35:^ lb. per mile, varying of course v/ith the size of the 

 engine employed to do the work, the smallest engines invariably 

 consuming the smallest quantity of fuel for the same work done. 

 The average consumption of coke during the half-year ending 

 4th July, 1849, was 31;; lb. per mile for passenger engines, and 

 4T-} lb. ])er mile for goods engines. These returns refer to a stock 

 of about 200 engines, and a length of line of about 310 miles. 



Thus the writer came to the conclusion that it would be possible 

 to construct a carriage and engine combined, of sufficient capacity 

 for l)ranch traffic, and by his advice the directors of the Eastern 

 Counties Railway gave orders to Mr. Adams to construct such a 

 carriage, subject to the approval of Mr. Hunter, the locomotive 

 sujierintendent. 



The carriage was accordingly luiilt, and called the EnfieM, from 

 the branch which she was intended to work. The engine has 8-in. 

 cylinders, and 12-in. stroke; driving-wheels 5 feet diameter; dis- 

 tance between centres 20 feet; width of framing 8 ft. 6 in. The 

 boiler is of the ordinary locomotive construction, 5 feet long by 

 2ft. Gin. diameter. The fire-box is 2ft. lO^in. by 2ft. 6in. There 

 are 115 tubes of Ig inch diameter and 5 ft. 3 in. in length, giving a 

 total of 230 feet heating-surface in the tubes. The area of the 

 fire-box is 25 feet, giving a total heating surface of 255 feet. The 

 weight of this steam carriage is 15 tons 7 cwt. in working trim. 

 The engine and carriage being combined, it is evident that the 

 weight on the driving-wheels is increased by the load carried, and 

 that this weight increases in the same ratio as the load required to 

 be taken. The extreme distance between the centres of the lead- 

 ing and trailing wheels being 20 feet, accounts for the steadiness of 

 this machine; there is indeed no perceptible oscillation when tra- 

 velling at the highest speed, and this verifies the observation "that 

 the steadiness of an engine depends not on the position of the 

 driving-wheel, hut upon the length of the rectangle covered by the 

 wheels." This engine at the same time daily traverses curves of 

 5 or 6 chains radius. 



The Enfield steam carriage was originally intended to convey 84 

 piissengers, hut as it was found that when she was put on as an 

 express train the passengers increased in number, a North Woolwkh 

 carriage was attached ca])able of conveying llti passengers, and 

 also a guard's break van, making provision altogether for 150 pas- 

 sengers, which is now her regular train taken at a speed of 37 miles 

 per hour. 



This engine commenced her regular work about eight months 

 since, and the following return shows the miles run and coke con- 

 sumed by this engine during the 7^ months' regular working from 

 January'29th to September 9th, 1849:— 



14,021 total miles run. 74.1 cwt. coke consumed in running. 



408 cwt. „ Btnniiing. 



280 cwt. „ getting up steam. 



1.4;i7 cwt. total col<e consumed. 

 2,162 total hours, in steam. lr48 iiis. per mile average consamplion of coke. 



The Enfield is in steam 15 hours per day, the fire being lighted 

 about six in the morning and drawn at ten o'clock at night. But 

 of these 15 hours it a|ipeai"s by tlie return that she is engaged run- 

 ning only five hours, tlie remaining ten being employed standing in 

 the siding. It was fcmnd by experiment that the quantity of coke 

 consumed standing was 32 lb. per hour, and after deducting this 



"t'.'J hours, running time. 

 1.4.')7 hours, standing time. 



and the quantity consumed getting up steam, it will appear that 

 the actual consumption of coke runnitig is under 6 lb. per mile. It 

 must also be particularly borne in mind that this consumption of 

 coke includes the total goods and coal traffic on tlie branch, 

 amounting to 1,410 tons — viz. 1()9 tons of goods and 1,241 tons of 

 coal. 



The EnfieM steam carriage worked the 10 a.m. passenger train 

 from London to Ely on 14th June, a distance of 72 miles, taking 

 behind her three of the ordinary carriages and two horse-boxes ; 

 she arrived at Ely 8 minutes before time, and the total consump- 

 tion of fuel, including the getting up steam, was found to be 8| lb. 

 per mile. The tubes of the boiler are only 5 feet 3 inches in 

 length, and the economy of fuel is consequently scarcely at the 

 maximum. 



Another engine on a similar plan to couple with a 40 feet carri- 

 age is now nearly re.idy, the tubes being 6 feet 6 inches long, from 

 wliich is expected even more economical results. 



The result of the writer's experience is the conviction, that for 

 express purposes, and for the larger portion of the branch traffic 

 on railways, the light steam carriage is the best adapted and most 

 economical machine, both as to first cost compared to the work 

 done, and in working expenses. 



The first cost of a large engine, tender, and four carriages has 

 been 4000/. The steam carriage for the same number can be made 

 for something less than one-half the cost. 



Remaris. — Mr. M'Connell gave much credit to Mr. Samuel for the 

 introduction of this branch traffic-carriage. If managers of railways could 

 always calculate the number of passengers to be carried, he (Mr. M'Connell) 

 could conceive that a great economy might be effected, even under the 

 present system. But this was impossible. How far, under these circum- 

 stances, Mr. Samuel's carriage might become useful, he was not prepared to 

 say. Undoubtedly with the present carriages the proportion of tbe tare to 

 the passengers carried was very great ; and although a case which rarely 

 happened, instances had occurred where the tare was 50 tons to 3 tuns of 

 passengers. But even taking the weight of passengers at 10 tons, 50 tons 

 of carriages was unquestionably a large proportion of dead weight to carrryj 

 and he considered that the long carriage, if always likely to be well em- 

 ployed, would be an advantageous mode of saving the dead weight, more 

 especially on branch lines, and at the junctions where such branches came in. 



Mr. Samuel further explained, that as Die length of coupling of the 

 engine-wheels in the Enfield was oidy 5 ft. 4 in., with an 8-inch cylinder, it 

 was necessary to attach the carriage and engine on one frame, otherwise it 

 would be too short to run steadily ; the effect produced by the carriage wa« 

 like the stick of a rocket in steadying the motion. But in the Cork and 

 Bandon engine with a 9-inch cylinder, the length. of coupling of the wheels 

 was 10 feet, and no carriage was required to produce steadiness, as the rect- 

 angle on the rails was so much longer. In the case of large engines, where 

 the distance between the axles had been increased to 16 feet, a greater 

 steadiness was observable. There was accommodation in the carriage for 

 15 first-class and 116 other passengers, giving a total accommodation for 

 131 passengers; and this he considered the most serviceable fur working the 

 express traffic. One of these steam-carriages was being prepared for working 

 on a railway in Scotland, at a contemplated speed of 40 miles an hour. Xt 

 the present time it was impossible to keep the road in good repair, especially 

 on tbe old lines, in consequence of the enormous weight of the engines. 

 The Enfield engine was worked at 120 lb. pressure, while in ordinary engines 

 it did not exceed 801b., and hence an advantage of 40 lb. was obtained. 

 The heating surface of the fire-box was 25 feet. He had, with the Enfield 

 engine, made the quickest journey that had ever been performed betweea 

 Norwich and London. With a train capable of containing 84 passengers 

 they performed the distance of 126 miles in 3 hours 35 minutes, including 

 stoppages. Another advantage in a large carriage of this description re- 

 sulted from making use of the side space, for there were only 8 wheels to do 

 the work of 24, and at the same time they had no greater amount of weight 

 on each wheel than under the ordinary arrangement. The whole weight was 

 9 tons without passengers, and 84 passengers might be taken at an average 

 as weighing 6 tons. 



The President considered that they were much indebted to Mr. Samnel 

 for his excellent paper, and he regretted that many interested in the econo- 

 mical working of railways had absented themselves from that meeting. The 

 subject of economical transit had, of course, occupied his attention, and he 

 must say, that, although he considered the suggestion of Mr. Samuel, so far 

 as certain branch lines were concerned, was entitled to the consideration of 

 all railway companies, yet he (the President) did not agree with Mr. Samuel 

 to the full extent. ()n small local lines — such as those from London to 

 Greenwich, and London to Blackwall — such carriages would he very valuable 

 in lessening the expense of working, but he could not agree in thinking that 

 for express purposes, or any other, such carriages would or should become 

 popular on main lines, lie could not agree with Mr. Samuel, also, with 

 reference to the necessity of fixing the engine to the carriage, for the pur- 

 pose of giving it steadiness. It appeared to be like riveting harness to a horse. 

 There was no mechanical necessity for it. He would advise Mr. Samnel not 

 to overstrain his principle by endeavouring to apply to trunk lines what 

 would be manifestly beneficial to branches. The public expected certain 



