Stantly apt to slip, and who endeavor to ||sion does on a railway; and that, under all But there is another consideration that Let us in fact examine the same engine, with the same weight and same pressure, placed in those two different circum stances. Why demur to lay out capital, if a considerable profit is to be derived from it? Why save the first expense, if the consequence is the necessity of spending more annually than the interest of the capital saved? This is exactly the present case. The construction of a railway is undoubtedly expensive; but it is the principal element of success. It is money employed to level the road, in order not to have any difficulty afterwards in conveying the goods, and to begin from that moment to reap the profits. What would be said to a man who should propose to cross the fields, in order to avoid the constructing of roads? The answer would be, that the loss in freight would be greater than the expense of conlbs. struction. The experiments made by Mr. Telford, on the draft of carriages on different sorts of roads, prove that on the road from Liverpool to Holyhead, the best in England, the force of traction necessary to draw a weight of one ton is as follows:-* 5th. On a broken stone surface upon a bottoning of concrete, formed of Parker's cement and gravel Mean 33 The same is true in regard to railways. If there be an advantage in constructing 65 them for horses, as an experience of sixty 147 years' prosperity has sufficiently demon strated, how is it possible that there should 46 be none for the use of locomotive engines or any other moter? Whatever advantage those engines may offer on common roads, they must necessarily present a much greater one on railways. 46 67 On a railway, a ton requires only 8 lbs. traction. Thus, on the Holyhead road, the traction of a ton requires eight times as much force as on a railway. all that can be supposed, even admitting improvemen s, for that force corresponds with 120 stage-coaches on a railway. We must take therefore two or three stagecoaches at most, as the regular load of these engines. But the levelling, which is the result of the expense attending the construction of a railway, renders those same engines capable of drawing 40 loaded stage-coaches or wagons. This is thus 12 or even 20 times as much. To do the same work on a common road, 12 times as many engines will consequently be required at once, with 12 times as many engine-men and fire-men. Considering also the disadvantage there is for the engines, in respect to fuel, in drawing small loads, we may confidently calculate that the expense for fuel will be doubled. Of this we will be the more convinced, if we take into account the surplus of power necessary to move the engine itself on a road full of asperities. Besides the repairs of the engines are, even on railways, a considerable expense. At Liverpool, of the 30 engines belonging to the company, ten only are in activity on the line for the conveyance of goods and passengers. The effective work is eight or ten hours a day, and the expense for maintaining in activity those ten engines, amounts to more than £18,000, or £1,800 a year for each of them. These expenses are paid and become a source of profit, because on a railway the engines draw considerable trains; but it would not be the same thing if the trains were reduced, or, in other words, if a greater number of engines were required to do the same work. Moreover, if the engines, instead of sliding without jolts on the smooth surface of a railway, were obliged to run on the rough soil of our roads, how great would not be the expense of repairs. And we have 12 times as many engines to repair. At Outlay and interest of capital for enIt may appear surprising to see a steam-gines, salary of engine-inen and assistants, engine on a common road draw two or fuel, repairs, all these articles will soon have absorbed the expected economy. three stage coaches with 12 or 15 passengers in each. But the Liverpool engines Besides, the chief advantage of such unat the time of the races have drawn as dertakings, consists in the speed with The consequence is, that the FURY en- much as 800 persons in a single train, at a which the haulage is executed. When gine, for instance, which by the effect of speed of 15 miles an hour. the 29 miles between Liverpool and Manits 65 lbs. effective pressure, was able to It will perhaps be said that steam-car-chester were travelled in four hours, there draw on a level 244 t., would in no cir- riages are able to draw more than three were about 450 passengers going daily cumstance, even on the excellent Holy-stage-coaches. As yet, however, none from one of those towns to the other. head road, be able at the same pressure to have been found that have done more present when, thanks to locomotive endraw more than of that load, or 30 t. The greatest part of them do not even gines, the journey is completed in an hour Thus its maximum load on a common carry more than 18 or 20 passengers. It or an hour and a half, there are 1,200 pasroad would only be the of its minimum is easy to see the cause that puts so soon sengers a day. The speed has the greatload on the railway. a limit to their load. There exists no comest share in the creation of that profit. It To which must still be added, that the mon road without considerable acclivities. must be given up if the engines are only to resistance of the engine in the case of its As they must be overcome, it is necessary run eight or ten miles an hour. progress on a common road, will be, like to give to the engine only the load which the resistance of the wagons, considerably it can take over the steepest of those asaugmented. It will therefore be obliged, cents. Now, on an acclivity of the in order to move itself, to consume a much greater portion of its own power, which will diminish in the same proportion the 30 t. it might else have drawn. Now, the 8 or 9 t. that the locomotive engines weigh on railways, allow us to give them a sufficient extent of boiler to weight of three stage-coaches, or 9 t., in- generate a certain quantity of steam per creased by the weight of the engine, pre-minute, and consequently a certain speed. sents, on account of the gravity, a resist. If the nature of the road obliges us to reince equal to that which 45 t. or 15 stage-duce the weight of the engine to 3 t. only, We see that on a common road, the re- coaches would offer on a level. A steam- with the necessity of making all its diffsistance of the carriages puts much quicker engine that is to draw three stage-coaches erent parts stronger, on account of the jolts a stop to the useful effect than the adhe-during a journey of some length, must on a rough surface, there will naturally be therefore be able to draw 15 loaded stage-less heating surface in the boiler, and concoaches on a level common road. This is sequently less possible speed. And, in . Report of the Holyhead Road Commissioners. than eight or ten miles an hour. fact, the steam coaches scarcely do more|| weights of water evaporated will then be being calculated once for all the given diAs a last reflection we shall add, that der, or, in other words, as the resistances on be necessary than to add that quantity to to each other as the pressures in the cylin-mensions of the engine, nothing more will until the present moment the success of lo- the piston. Besides as the water is first M and M', in order to have the required comotive engines on common roads, con-transformed into steam at the pressure of proportion of Q to Q'. tinues, as a speculation, to be very uncer-the boiler, that is to say, in both cases into tain, whilst the prosperity of railways, whatever be the moving power, is demonstrated by their continued extension. Steam-coaches may be improved, but, we repeat, whatever be the advantages they may offer on a common road, it is not This shows that the consumption of fuel to be contested that, by employing them on is independent of the speed, and that it dea railway, those advantages will be infi-pends only on the resistance on the piston. nitely greater. CHAPTER IX. OF THE FUEL. § 1. Of the Consumption of Fuel in portion with the Load. steam at the same degree of pressure, it have an engine similar to the 11-inch cy- If in the two journeys we consider, the pressure happens not to be identically the same in the boiler, there will be a little more fuel consumed in that case where the pressure has been the greatest, because the pressure could only increase in consePro-as degrees of pressure very distant from quence of an increase of temperature. But each other are produced by very similar temperatures, the difference of consumption occasioned by that circumstance will be of little importance, and will not be perceived in practice. We have still an important article to dis- cuss. From what we have said above, the steam generated in the boiler at whatever pressure it may be, takes, in passing into This principle gives the proportions of the cylinder, a pressure exactly determined the consumption of fuel for the same enby the resistance on the piston. The mode gine with different loads, and may thus of action of the engine, is thus limited to serve to determine its consumption in all the transformation of a certain quantity of circumstances, as soon as it is known in steam, drawn from the boiler, and conse-one determined case. quently at the pressure of the boiler, into steam at a lower pressure and of a proportionally greater volume. If for instance Q and Q' are the quantities of fuel expended with two given loads, the resistance on the piston with the first of these loads being expressed by R, and with the second by R', we shall have Q R R Let us suppose the same engine, with the same pressure in the boiler, and travel ling the same distance with two different loads. The distance travelled being the sa.ne, the number of turns of the wheel, and consequently of strokes of the piston or cyBut we have already calculated the resislinders of steam expended during the jourtance R on the piston of an engine. We ney, will be the same in the two cases. have seen (Chap. V. Art. II.) that M beIf the load had been the same, there would ing the load expressed in tons, tender inalso have been identity in the nature of the cluded; F the friction of the engine withsteam expended. But as the loads differed,out load; d the diameter of the cylinder; the same number of cylinders will indeed the diameter of the wheel; 7 the length have been expended, but the degree of the of the stroke; p being the atmospheric steam in the cylinders will be different in pressure per unit of surface, n the resisthe two cases. tance of the load per ton, and & the additional friction of the engine per ton of load, Then the expense of moving power will be in one case a certain volume of steam at the pressure R, for instance, and in the other case the same volume at the pres sure R'. same. The pressure of the steam in the boiler being supposed the same in the two experiments, its temperature will also be the As the temperature experiences no reduction during its passage to the cylin ders, the pipes and the cylinders themselves being immersed in the boiler, or sur rounded by the flame of the fire-place, the temperature of the steam in the cylinders will be the same in the two cases. that resistance is D del P. is nothing but the fric R = [F+ (8 + n) M] tion of the engine and the atmospheric pressure referred to the velocity of the enThus, for a different load drawn by the gine, and represented by the number of same engine, we shall have This equation can be written in the fol-be added to the load, expresses, as we have Thus the volume and temperature of lowing form: the steam expended during the journey will be the same in both circumstances. The pressure of the steam in the cylinder will alone have undergone a change. Consequently the mass or weight of steam expended, will be in each case in the ratio of the pressure in the cylinder. The weight of the steam being equal to that of the water that generated it, the Q M + + (d+ n) D F F M' + { (8 + 1) D + Sothat the expression s + n said, the aggregate inert resistance of the engine, or, if we may be permitted to use that expression, the constant vis inertiæ of the engine. As this quantity differs for each engine, and as it must be calculated separately for each of them, we shall join here a table which will show its value, superseding thus the necessity of calculating it, for the engines most commonly used on railways, might be taken into consideration. ▲ TABLE OF THE CONSTANT VIS INERTIE der was weighed with the same care as at|| tender, in order that those circumstances Designation of the Engine. Engine with cylinders 11 in., Constant As an engine that ascends alone, with its train, an inclined plane exerts necessarily a greater effort than if at that moment it were helped by an additional engine, we vis inertia, have put down whether the engine was expressed helped or not in going up the plane. We have also inscribed the state of the weather and the temperature of the water in the in tons. In these experiments, the co-operation of the persons attached to the establishment was often necessary. We must particularly mention Mr. J. Dizon, the resident engineer, to whom we are indebted also for his accurate levelling of the road, and many other pieces of information obligingly communicated to us. 5 ft. § 2. Experiments on the Quantity of Fuel consumed by the Engines. The above formula, which is of easy application, gives the absolute quantity of fuel required by an engine in all circumstances, provided the consumption of the et gine in a given case be known. The only thing necessary, will therefore be, to make one experiment on the fuel consumed by the engine with a given load, which will be the data of the problem. Evidently between two different engines, this first data will differ according to the particular construction of each engine, and chiefly according to the extent of heating surface of its boiler. The following experiments were therefore undertaken on the Liverpool and Manchester Railway, in order to obtain a knowledge of this data, and likewise to verify the thecretical principle exposed above. In these experiments the tender was first carefully emptied, then the coke was accurately weighed and put into the tender. The fire-place of the engine was besides filled with fuel, up to the lower part of the door. At the end of the experiment, the fire-place was again filled to the same height, and the coke remaining in the ten 80 t. EXPERIMENTS ON THE QUANTITY OF FUEL CONSUMED BY THE LOCOMOTIVE ENGINES, WITH GIVEN LOADS. 53.7 1596 0.28 Help. Cold in the tender. Calm. 53 1102 0.34 Help. Lukewarm in the tender. 66 0 53 1224 0.34 Help. Cold in the tender. Fair and calm. The Do. do. 94.66 1.25 and 4 empty from M. to L. 31 July 8 loaded wagons 35.15 1.54 17 July 3 loaded wagons 1136 0.33 Help. 1118 0.32 Help. connecting rods of the wheels too tight. Fair and calm. Lukewarm in the tender. One piston too slack. Little lukewarm in tender. Calm. 66 1012 0.52 Help. Very hot in the tender. Fair and calm. The axle-box of one of the wagons too tight. 0 30 881 0.73 No help. 86 EXPERIMENTS ON THE QUANTITY OF FUEL CONSUMED BY THE LOCOMOTIVE ENGINES, WITH GIVEN LOADS. In examining these experiments, we find the coke employed was of prime quality, or that neither the pressure in the boiler, nor the velocity of the motion, have any remarkable influence on the result. This fact was already indicated by theory. It of the atmosphere, the engine, and its tender. We must add, that in those experiments Respecting the distance travelled by the engines in these experiments, the railway from Liverpool to Manchester is generally reckoned 30 miles long, and considered a level; but as a greater degree of accuracy is required in the calculation, and as we wish to deduce from these experiments the really corresponding consumption of coke on a level railway, we must reckon as follows. One part of the line travelled by the lo- 1 t. at 26 miles, on nearly a 1 t. at 11⁄2 mile, ascending 1 at 26 1 at 6 1 t. at 1 mile, descending by Sum - 1 at 32.5 Thus when the engines ascend the plane without help, the work they actually do is equal to the traction of a similar load to a distance of 32.5 miles on a level. If they ascend the plane with the help of one or more other engines, their share of the load in ascending is on an average only of the whole on the plane, and thus the work they do is equal to the traction of their load to 26.5 x 2 28.5 miles. This does not include the surplus of resistance owing to the gravity of the engine and its tender in going up the plane. Their average weight being together from 13 to 14 t., the gravity of which on the plane is equal to the resistance of about 40 t. on a level, we see that this fresh effort required of the engine, equals the traction of 40 t. to a mile and a half, which is the length of the acclivity. If, therefore, the train itself weighs 30 t. without the tender, as is the case with engines that are not helped by additional ones, the work is equal to the traction of that train two miles more than the length of the line. If, on the contrary, the load weighs 60 or 80 that are helped on the inclined planes, the t., as is in general the case with engines additional traction of 40 t. for 1 mile, is equal to the traction of the whole load to Worsley coke, which is prepared on purpose We also remark the advantage that is the passage of the inclined planes, we Then for trains that receive no help at must reckon the distance for which the draft has taken place, as equal to 34 miles on a level; and for the engines that are helped on the acclivity, we must reckon traction of their load to a distance of 291 the work they have done as equal to the miles on a level. The difference which exists in these two cases, is of in plus for the unassisted engines. This is the work done by the helping engines, when they It is from those distances of 29.5 miles and 34.5 miles, that the numbers placed in the eighth column of the preceding table have been deduced in each experiment. In examining the results contained in that table, we find that they agree with the rule deduced above from the theory of the engine. establishment. are employed, and the surplus of work pro-suring the pressure of the steam; of calcu-used for putting together Locomotive Enduced by the passage of the planes. lating the load, the velocity, and the pro-gines. Several of the best Engines in use portions of the engines; of valuing the dif- in the United States have been put in this ferent sorts of resistance they have to over- No. 4. A three story brick building, cov. come; of taking into account the influered with slate, 120 feet by 46, containing ence of additional circumstances on their two water-wheels, equal to 40 horse power; motion; and, finally, of knowing their con Machine Shop, filled with lathes, &c.; Patsumption of fuel. tern Shop; Rolling Mill and Furnaces, caHere naturally our work terminates. pable of rolling 4 tons of iron per diem, exHowever, as a knowledge of these enginesclusive of other work; three Trip HamFor the ATLAS, the average of the ex- cannot be complete, unless we are able mers, one of which is very large; engine for blowing Cupola Furnaces, moved by waterperiments made with 25 wagons, gives to calculate also the expenses they will re-wheel; one very superior 12 horse Steam 119 t. conveyed by 1136 lbs. of coke. Calquire for a given draft, we add in an Ap Engine, which could be dispensed with; culating upon this data, and adding for pendix the necessary information, by means and a variety of other machinery. the cases where there has been no help, of which that important point may be established. we find tons. lbs. Calcula- Experi 774 190 and tender 95 and tender 65 and tender 1531 881 720 51 and tender 806. 664 MR. FESSENDEN, No. 5. An Iron Foundry, 80 feet by 45, with a superior air Furnace, and two Cupo. las, Core oven, Cranes, &c. fitted for the largest work. Attached to the Foundry is a large ware.house, containing Patterns for the Castings of Hydraulic Presses, Locomotive and other Steam Engines, Lead Mill Rolls, Geering, Shafts, Stoves, Grates, &c. These were made of the most durable ma terials, under the direction of a very scientific and practical Engineer, and are supposed to be of great value. a Sir-I send you for distribution, though perhaps, rather late a few squash seeds, which I obtained in Illinois last season. No. 6. A building, 65 feet by 36, containing They are known there by the name of the large stack of chimneys, and furnaces, for "Potato Squash," resembling very much making Cast Steel. This building is at the sweet potato, being very dry and sweet present used as a boarding-house, and can 690 to the taste. If they can be raised here as accommodate a large number of men. No, 7. A range of buildings, 200 feet long by well as there, they will surpass all others. 36, containing counting room, several store I ate of them mashed as we mash our common potato, and their flavor was exceed-rooms, a Brass Foundry, room for cleaning castings, a large loft for storing patterns, ingly fine. They grow about the size of stable for two horses, &c. &c. the common short necked squash, and weigh about six pounds; their color nearly white. Respectfully, 746 759 If we take into account the accessory circumstances, we shall find between the calculation and the experiment, as complete a coincidence as the nature of the experiments themselves could allow; for, besides the above-mentioned circumstances, the greasing of the carriages, the quality of the coke, and, above all, the manner in which the fire-place is filled after the experiment, are subject to produce considerable differences, notwithstanding the most scrupulous attention. The experiments we have related, give the quantity of coke consumed during the trip. The above establishment being on tide water, presents greater advantages for some kinds of business than any other in the United States. Coal and Iron can be carried from vessels in the harbors of Boston, to the wharf in front of the Factory, at 25 to 30 cents per ton. Some of the largest jobs of iron work have been completed at this establishment; among others, the great chain and lift pumps for freeing the Dry Dock at the Navy Yard, Charleston. The situation for Railroad work is excellent, being in the angle formed by the crossing of the Providence and Worcester Railroads. The Locomotive "Yankee," now running on the latter road, and the "Jonathan," purchased by the State of Pennsylvania, were built at these works. With the Patterns and Machinery now n the premises, 12 Locomotives, and as many tenders, besides a great quantity of cars and wagons, could be made per annum. For terms, apply to THOS. J. ECKLEY,Treas.&c. Boston, or to ROBERT RALSTON, Jr. Phila. j25-4t Boston, April 21, 1835. It is however clear, that in the interval between one trip and another, the engine, although at rest, continues to consume a certain quantity of fuel, because its fire must be kept up for the following journey. It is true, that several of those engines, such as the ATLAS, VESTA, and some others, have a particular sort of apparatus, by means of which, while the engine is at rest, the steam that continues to be generated in the boiler may be led to the tender. That steam is then not completely THE SUBSCRIBER is authorised to sell PAGE'S MORTICING MACHINES, to be used in lost, being condensed in the boiler, and serving to heat the water it contains.' But any of the Western, Southern, or Middle States, (except New-Jersey,) and also to sell Rights for Towns, Counties, or States, in the same region, including New-York. MACHINES will be furnished complete, ready to work, and at a liberal discount to those who purchase territory, or machines to sell again. No. 3. Locomotive House, 54 feet by 25, 132 Nassau street, New-York. Terms of single machines, $30 to $35, for common morticing; and $50 to $60 This is a practical piece of information for HUB machines, which, in the hands of an experienced man, will mortice 14 to 16 which will find its place hereafter. The researches contained in the work, give the solution of all such questions as are most important for the application of locomotive engines to the draft of loads on setts of common carriage or wagon hubs per day. WILL be published, in a few days, NICHOLSON's Treatise on Architecture.- railways. They give the means of mea- Also, PAMBOUR on Locomotive Engines on Railroads. |