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Mechanics' Magazine, MUSEUM, REGISTER, JOURNAL, AND GAZETTE.

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DESCRIPTION OF AN IMPROVED PLAN OF RAILWAY SUPERSTRUCTURE ADOPTED ON THE BALTIMORE AND OHIO RAILWAY. BY BENJAMIN H. LATROBE, ESQ., C.E. WITH REMARKS BY ELLWOOD MORRIS, ESQ., C. E.

(From the Franklin Journal for March, 1842.) The rail is of rolled iron, imported from diameter, and going quite through the three England; it is of the bridge, trough, or timbers; but where the joinings of the coninverted U section,* 3} inches in height, tinuous bearing occur above a tie, two free47 inches in width at the base, and 2} inches nails of an inch in diameter (one in each of from out to out of the sides of the upright the meeting ends of the continuous bearing) stems; the bars are in lengths of 20 feet,

are used. with their ends cut square, and weigh 340 The joinings of the rail-bars upon the oppounds each, or 51 lbs. per lineal yard. posite sides of the track, break joint with

The rolled iron rail is supported through each other midway of their lengths; they out its length, by a continuous bearing of also break joint at the same time with the sawed timber, 41 by 8 inches in section, and continuous bearings upon which they rest, in lengths of 20 feet, like the rail-bars and and these in like manner break joint with sub-sills.

the sub-sills ; every joint of two adjacent The continuous bearing reposes flatwise timbers of the continuous bearings, is made upon cross-ties and bearing-blocks, the cross to fall upon a cross-tie, and all the joinings ties being 41 by 6 inches in section, laid in the track are merely square butt joints, flatwise upon the sub-sills, and notched on no scarfs being used; by this system of disthe top 11 inch deep and 8 inches wide, to tributing the weak and strong points, the receive the continuous bearing ; this notch strength of the track is equalized. being cut fths of an inch deeper on the side A cast iron joint chair, weighing 74 lbs. next the centre of the track, so that the is placed under the ends of every two adcontinuous bearings when laid on both sides, jacent rail-bars, and a centre chair, also of mutually decline towards each other at the cast iron, weighing 4 lbs. under the middle rate of Eths of an inch in 8 inches, or 1 in of each rail. 13, thus bringing the top of the iron rail The joint chairs, together with the rail. also, into a plane of this inclination, which is bars, are fastened down on the continuous the same as that of the cones of the wheels bearing by two vertical screw-bolts, (one on now used upon the Baltimore and Ohio Rail. each side of the chair) going through oblong road.

mortise holes made in the timber, and also, The bearing blocks are 3 by 6 inches in through similar apertures in cast iron bear. section, and 1 foot in length, they are laid ing-plates, fastened up against the bottom of crosswise to the track upon their flat sides, the continuous bearing, in the interval beand support the continuous bearing at points tween two supports, but close to one: the intermediate to the ties, without any notch screw-bolt is formed with an oblong square ing:

head, fitting the mortise hole in one direction The cross-ties are laid 5 feet apart be. only, so that by making a half turn with it tween their centres, as are the bearing blocks, after its head has descended below the bear. and hence, the continuous bearing is sup ing plate just mentioned, it laps over the ported at points 21 feet asunder, if we mea sides of the oblong hole in that plate, and sure from centre to centre of the supports, falling into a recess cast for the purpose, or has unsupported spaces, of but 2 feet li when drawn up by the nut, the bearing neal in the clear between the sides.

plate is thus made to grasp the continuous The cross-ties and bearing-blocks rest bearing firmly: whilst the nut being screwed upon sub-sills, 3 by 10 inches in section, down upon a wrought iron washer and zinc and also in lengths of 20 feet; at every point plate, (designed to protect the iron by gal. of support, the continuous bearings, the vanic action) which lap upon the projecting cross-ties or bearing blocks, and the sub-sills, base, or feet of the contiguous bars of the U are pinned together by tree-nails 14 inch in rail, they are thus secured to the joint chair,

and the latter to the continuous bearing.

The centre chair, and the middles of the • This pattern of rail, which in section very much resembles the letter U inverted, and hence,

rails-bars, are held down on the continuous in technical phraseology, ought perhaps to be called bearing by four brad-headed spikes, (each the U rail, was invented by S. V. Merrick, Esq., of Philadelphia, in 1831, and by him denominated the

4} inches long and lo square in the shank ;) Trough Rail from its resemblance, when inverted,

and the iron rail between the joint and to a trough. (See the Franklin Journal for August, centre chairs is held by twelve similar spikes 1835.) It has been used upon the Wilmington and driven in pairs, (one on each side) at interSusquehanna Railroad, and the Great Western Railway in England, and continues to give very satis

vals of 23 feet. factory results.-ED.

The chairs are let their own thickness

LATROBE'S IMPROVED PLAN OF RAILWAY SUPERSTRUCTURE. 371 (fths of an inch) into the continuous bearing, through the rib of the bearing plate ; M, so that their tops are flush with the upper plan of the nut and washer. surface of the latter, and the bottom of the Scale of A, B, and C, 4th of an inch to rail bears fairly upon both.

the foot, the remainder, being the details, The chairs have each a projection going are drawn quarter-size. up vertically into the hollow of the rail, and two horizontal semi-circular projections on their ends to fit into half round mortises in Remarks by Ellwood Morris, Esq., C. E. the wood, to prevent lateral motion.

We invite attention to the foregoing plan The centre chairs, moreover, have two

of railway superstructure, as embodying square projections on the upper surface, which fit notches of the same dimensions

in a great measure, the experience acquired (Eths of an inch square) in the feet of the

by the railway practice of the country:* rail, to confine the bars from longitudinal

In 1838, Messrs Knight and Latrobe, the

distinguished engineers of the Baltimore and movement. The whole of the track is laid upon, and

Ohio Railroad, were specially commissioned

to visit the most important railways in the partly imbedded into, a ballasting of broken

United States, with the view of availing stone, composing a mass of open material

themselves of the experience of the whole entirely pervious to water-10 feet wide at bottom, 8 feet at top, and 1 foot in depth :

country, in framing a plan for a new track,

then about to be laid between Baltimore and the lower part consisting of stone broken to

Frederick, to replace the original superstrucpass every way through a 2 inch ring, and

ture, of which the wood work had decayed the upper part of such as will in like man

and required renewal, and the stone continer pass a 4 inch ring: the base of the ballasting is about 4} inches below the bottom

nuous bearings had ceased to give satisfac

tion. of the sub-sill, and its top, level with the

The results of the observations of these upper surfaces of the cross-ties, or 3 inches below the top of the continuous bearing. The

engineers were reported to the Directors of

the Baltimore and Ohio Railroad Company, distance between the iron rails, or the gauge

in an able and elaborate memoir they disof the railway, is 4 feet 81 inches.

cussed in detail the merits of the various plans of railway which came under their observation; and ultimately recommended a superstructure having a sub-sill and crossties, surmounted by a rolled iron H rail of 50 lbs. to the yard, in lengths of 18 feet, with angular joints, and for which the crossties formed isolated bearings of 2} feet asunder, from centre to centre, except at the ends of the bars, where the bearings were made but 11 feet, conformably to Barlow's experiments; this superstructure was de

signed to be embedded in a broken stone D

ballasting, of 1 foot deep; and many miles upon this plan were laid in 1839, and have since been in constant use.

Though there are, of course, some variations in the details of the fastenings, &c., the superstructure above described differs from that adopted in 1838—at the suggestion of the same gentlemen-mainly in two

particulars : References to the Engravings. A, general plan of the superstructure; B, • From an inspection of the railways of general side view of ditto ; C, transverse section

trade, which have been the longest in use, the

writer is strongly disposed to conclude, that it will ditto ; D, side view at the joint of the rail,

eventually be found advisable in such railroads as showing the rail and its fastenings to the carry a very heavy traffic, and the earth works of contiguous bearing; E, cross section through

which have acquired the requisite stability, to lay

the superstructures in a bed of concrete, as has been the continuous bearing at the joint of a rail ;

suggested in the London Mechanic's Magazine ; the F, plan of the joint chair ; G, end view of expense of which, in such cases, would probably be ditto ; H, plan of the centre chair; I, end compensated by the additional smoothness of surview of ditto; J, plan of the bearing plate ;

face, and freedom from derangement, which such a

foundation might fairly be expected to impart to K, plan of the screw bolt; L, cross section railways.

B B 2

1. In having a continuous bearing of postponed, and not annihilated, by any timber beneath the rolled iron rail, upon change of form or pattern ; still it must be which it rests throughout its length. admitted, that if the top table of the rail bad

2. In the adoption of the U bridge, or been so supported as to prevent it from being trough section, for the iron rail, in lieu of forcibly disrupted from its vertical stem, and either the T or H patterns.

thus render it subject alone to the natural These two essential variations from the exfoliations, which occur when malleable iron plan of the railway superstructure, recom is exposed to a series of great rolling weights, mended by Messrs. Knight and Latrobe, in the durability of that railway would have 1838, are fully justified, if not absolutely been essentially increased. demanded, by the practical experience upon The sort of support to the head of the these points, now dawning upon the country; rail, which practice now shows to be neceswhich at an earlier period in the history of sary, is given by the double stems of the U railways could not perhaps have been fore section, and not by the single one of the T seen, and certainly was not anticipated. figure ; consequently, it seems to the writer,

With regard to the first point, a close ob. that experience on existing works demands servation of such of the American railroads in future ones the adoption of the former as have been the longest in use-possessed pattern, in outline at least ; for it is a ques. of the largest trade--and travelled by the tion which time alone can determine, whether heavy locomotive steam engines, which are we shall not finally come to a solid bar rail now so common, will fully satisfy any pro. as the best ; for the present, however, it will fessional man, that the alternate succession probably be the proper course to use the U of rigid points and flexible spaces," which rail as now rolled hollow, in which form, as inevitably results from the employment of it can be made as light as the T and H patisolated bearings, tends to a more rapid de terns, its superior durability will gradual. struction, both of the locomotive machinery ly cause rails of the latter figure to pass and of the road itself, than is likely to ensue, from use, and give place to those of the where the iron edge rails are sustained upon former pattern, unless a superior section continuous bearings of timber of heavy pro should meanwhile be introduced. portions; which plan has also the recom To support these views, it would be easy mendation of having already been practically to cite further examples of the decay of rails tested upon the Baltimore and Port Deposite, of the T and H forms; but it seems scarcely and Washington branch railroads in this to be necessary, and upon the whole, we are country, and the Great Western, and Lon. disposed to conclude that the experience of don and Croydon railways in England the country, up to this time, indicates the with satisfactory results in each of these propriety of adopting, in future railway su. cases, so far as the writer is informed-be perstructures, a continuous bearing of timber sides being employed upon some other im. laid with a U rail, upon a suitable substrue. portant railways in America, which are now ture, in preference to any of the other plans in the course of construction.

now in use, most, if not all of which, seem Concerning the second point, or the sec on trial to possess fewer practical advantional form of the rail-we will observe that tages. the top table of the bars, upon which the In fine, the new superstructure of the wheels run, in the T and H forms—being Baltimore and Ohio Railroad appears to supported in the centre alone by a single combine in its plan a sufficient provision to upright stem, in thickness about one-fourth satisfy the most important requisites, in faonly of the width of the head-soon crushes vour of which the railway practice of the off on one side or the other of the centre, country has pronounced, viz. – and renders it necessary to reverse the po 1. That to guard against disturbance by sition of the bars.

frost or rainy weather, the superstructure On the Baltimore and Ohio Railroad, as ought to be embedded in a ballasting, enthe writer is informed, already has occasion tirely pervious to water, and of a sufficient been found to reverse the position of a num depth. ber of the bars (of the track laid with the 2. That to prevent the track from spread50 lbs. H rails in 1839) whose inner flanges ing laterally, numerous cross-ties should be have partially peeled off ! and upon the Co. employed. lumbia Railroad, which has been but seven 3. That to prevent unequal settlement of years in use, rolled iron rails of the T and the cross-ties, (which also form detached H forms may be seen in every stage of supports for the rails or continuous bear. destruction; and though a portion of the ings,) sub-sills of wood are indispensable. disintegration which may there be witnessed, 4. That to render the road more smooth, is undoubtedly owing to the intrinsic struc more equal in strength throughout, capable ture of rolled iron, and hence can only be of carrying greater weights than roads of

MESSRS. LILLIE AND SONS' BOILER FURNACE.

373 isolated bearing, and exempt from “ rigid more regular supply of steam"(with Parkes's points and flexible spaces," continuous bear. plan of furnace and air feeder by a double ings of timber ought to be employed to carry or hollow bridge,) from 13 lbs. of coal per the iron rail.

hour; a saving, in this instance, of 35 per 5. That the iron rail itself ought to be of cent. ; but what they strangely “ estimate at the U pattern, (either hollow or solid,) as 20 per cent. average.” Now Stanley's plan superior in durability to any other known has nothing to do with the admission of air, form of section now in actual use, whilst it which is the very essence of Parkes's plan. is very stable in position, and cheap in its Stanley's is in fact but a mere mechanical fastenings, when properly laid.

feeder, and is any thing but a “smoke i 6. That the iron rail-bars ought to be burner." firmly fixed at their middle parts, to cause “ H. H.” concludes by “relying on your expansion and contraction to take place both willing co-operation to make this very useways from their centres.

ful plan as extensively known to the public as it is freely presented to them.” To this I have only to add, that this plan so freely presented to them may be seen in the Lon.

don Journal of Arts as the undoubted and MESSRS. LILLIE AND sons' BOILER FUR

legal property of Josiah Parkes, the paNACE-INVENTED BY MR. PARKES.

tentee; and that “H. H.” has no right to Sir,- In your 976th Number, I observe a claim merit for presenting to the public letter from your correspondent, “H, H.," what did not belong to him. from Manchester, accompanied by an en Query. Was this the boiler which lately graving, in which credit is taken for the exploded on Messrs. Lillie's premises, owing, furnace, as an invention of modern date, as was stated at the time, to a deficiency of Now, sir, I cannot avoid stating that your water? correspondent, while he takes credit for

I am, Sir, yours, &c., “simply communicating the result of private

P. and personal experience, without fee or Manchester. reward," has omitted to mention that this very plan, as adopted by Messrs. Lillie and Sons, is neither more nor less than that of Mr. Josiah Parkes, patented above twenty

MESSRS. LILLIE AND SONS' BOILER years ago—it is, in fact, as given in your last Number, identical with Mr. Parkes's Sir, I have read in the number of your patent.

Magazine for the 23rd of April, the letter of It may just be possible that your corres. your correspondent “H. H.,” which is so pondent was not aware of the fact. In jus. calculated to mislead, that I feel assured tice therefore to Mr. Parkes, I beg to add you will readily admit a correction of its this fact to those stated by “ H. H.” In absurd errors, in relation to “ Messrs. Lillie this instance we have a striking corrobora and Sons' Boiler Furnace," and certain trials tion of the truth of your observations res of “ Stanley's Feeder." pecting the injurious effect of the “ Leeds Your correspondent has made a wholesale Smoke Nuisance" pamphlet, which has thus appropriation of the paper in Mr. West's brought forward, under the name of Lillie pamphlet without acknowledgment, and has and Sons, a plan of twenty years' standing, thus managed to make what was already and which, though possessing unquestion sufficiently mysterious in itself still more able merit, and in many instances eminently confused. The case appears to be simply successful, under careful management and this: Twenty years ago Mr. Josiah Parkes good " looking after," has, nevertheless, not introduced a split bridge, admitting a sheet carried the public with it, and has literally of air to the gases immediately as they passed gone into disuse since Mr. Parkes himself over the bridge. This plan, long practised, ceased to take any interest in the matter. is exceedingly well known. At Messrs.

“H. H." informs us that “a similar plan Horrocks' and Co., Preston, it has been may be also seen at Messrs. Horrocks', of used ever since its first introduction. This Preston." It would have been but common plan of Mr. Parkes', Messrs. Lillie and candour to have stated that that very fur Sons', engineers, have introduced at their nace of Messrs. Horrocks' was actually works, in Store-street, Manchester, their erected under Mr. Parkes's own direction. furnace possessing no other recommendation

" H. H." observes that “ in a former than good workmanship, for certainly no furnace which they had with Stanley's feeders, improvement of any kind affecting the prin. the consumption of coal was 20 lbs. perciple of the invention have they introduced. horse-power per hour; they now have a The very same kind of furnace, as set up

FURNACE.

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