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New Brunswick History and Other Stuff

A Proposal for a Wooden Railway

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From the blog at https://johnwood1946.wordpress.com

A Proposal for a Wooden Railway

The railway was a new technology in the early 1800s, and only slow progress was made at first in bringing it to North America. There were some early so-called railways with horses or mules, or even sails as motive power, but nothing more than that. A few steam locomotives had been imported from England for display purposes or for experiments but those experiments were not successful. There was only one steam locomotive manufactured in the United States but it too was only to prove the technology in American conditions which included curves routinely up to 15º or even up to 30º.  The builder of that first American locomotive acknowledged that it was “a very small and insignificant affair”. That was in 1829 and 1830.

The concept of railways was irresistible, however, and 1830 and 1831 saw a rapid deployment of locomotives built in the United States. In retrospect, then, the introduction of steam was not as slow as it was well-considered. After all, Stephenson’s improved steam locomotive only became available in 1825. The appended report was written in 1847 and, by that time, railways were being built at a frantic pace.

New Brunswick also wanted to build railways but there was already a lot of catching up to do. The earliest attempt came with the founding of the Saint Andrews and Quebec Rail Road Association in 1835, but their proposal did not advance very quickly.

By 1847 there was another proposal to build a rail line and a telegraph between Halifax and Quebec, and the government of New Brunswick commissioned a book of reports to be prepared on the subject. One of those reports was to describe U.S. experiences in railway construction and was written by John Wilkinson of the Surveyor General’s office in Fredericton. This blog presents John Wilkinson’s report which turned out not to be a balanced description of U.S. experiences, but strongly advocated for one particular method of construction.

The reader may decide whether Wilkinson should be congratulated for the strength of his convictions, or whether those convictions were ill-advised even at the time. In any case, if his recommendations had been carried through then they would not have become a model for the emerging industry. John Wilkinson’s report follows:

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Report to His Excellency Sir W.M.G. Colebrooke, K.H., &c., &c., &c. on some of the results of experience in the United States, with regard to the use of wood in the construction of railways, and with reference to the construction of similar works in the Province of New Brunswick

by J. Wilkinson of the Surveyor General’s Department, N.B.

– – – – – – – – – – – – – – – – – – – – – – –

Fredericton, 17th March, 1847

May it please Your Excellency, —

Agreeable the instructions communicated to me by direction of Your Excellency on the 8th January last, I have now the honor to submit such observations on Railway experience in the United States as may be useful in this Province.

The pressure of time on this occasion does not permit me to treat the subject either as fully, or with so much care, as I should otherwise desire. But any further information in my power to communicate is at Your Excellency’s command.

In the construction of public works, it is doubtless the wisest policy to have regard to the utmost degree of perfection consistent of circumstances and a well-considered economy. Hence the costly degree of perfection generally exhibited in such works in Great Britain and other portions of Europe, and also in the older parts of the United States, where population, trade, manufactures and wealth so largely disproportionate to the corresponding circumstances here. For this reason there are but few of the more perfect models which we are competent in all respects to imitate. We can understand and profit by the same principles, but the same details of application are, as a general rule, not expedient.

But it does not necessarily follow that we must wait until our social conditions be advanced to that of older countries, in order to enjoy, in many respects, equally the advantages of science and mechanical skill in our public works. We are, on the contrary, surrounded by inducements and by natural advantages, which, though associated with some difficulties, hold out the promise of ample success to well directed industry and enterprise, even with very moderate extraneous aid.

The enormous expense of the first Railway experiments in England for the transport of both passengers and freight, did not divert our neighbours on this side of the Atlantic from the incalculable advantages which were assured by an improvement so great and so peculiarly adapted to this Continent. On the contrary, they immediately began to consider the means within their reach of securing its benefits. They had the advantage of experience, purchased so liberally by British enterprise, and also natural advantages of their own, not available in England. In New England, indeed, where population, wealth, and local circumstances, amply justified the attempt, railways were begun and finished very closely after the English model. But in South Carolina, where the abundance of timber and the favorable character of the country naturally suggested the idea, timber foundations, and also rails essentially of timber, were adopted to obviate the costly alternatives of earthen excavations and embankments, solid masonry, and the heavy iron rail.

A line of this kind was constructed between Charleston and Augusta, 136 miles, within the years 1830 to 1833. Descriptions of the road, more or less particular, are given in some of the published official reports in relation to the work, on the authority of which I believe that dependence may be placed.

The result appears mainly to have fulfilled the expectations of the projectors, leaving no material difficulty to be provided for besides the consequence of the perishable quality of the structure, which was well understood and anticipated. It was necessary that all the timber should be periodically renewed, or that permanent earthen embankments and masonry should be supplied. The latter alternative was adapted, and the road being in full operation afforded facilities for embanking which rendered the cost comparatively light. But it does not appear from the experiment, that had any certain means of preventing the decay of the timber been known and made use of, that any necessity for embanking would have arisen for an indefinite period, if at all.

The manner of construction was, upon well-driven piles when the ground was soft, upon trestles when firm and solid, and simply on longitudinal under sills united by cross-ties, when excavations occurred, or where the grade coincided nearly with the natural surface.

Besides the exceedingly small expense, the advantages of this method in superseding, to a great extent, the necessity of bridges, culverts, and drains, and in avoiding the disasters which are so liable to be the result of any insufficiency in these structures, appear to have been very deserving of notice. The adaptation of the plan to large portions of this Province, and to similar descriptions of country everywhere, will appear by the following extract from the Report of the Commissioner of the South Carolina Rail Road, dated May 1st, 1838, being after the first year of trial of that Road:—

“The plan adopted in the construction has been peculiarly fortunate; it has been emphatically called the ‘Inland Bridge’—recently it has proved itself so. At a time when every mail teemed with accounts of the disasters occasioned by the late heavy freshets; when the Savannah River rose higher than it has done since the memorable Yazoo freshet; when serious apprehensions were at one time entertained for the safety of the Augusta Bridge; when the houses in Hamburg were encompassed by water, and all communication between Hamburg, Augusta, and Barnwell Court House was suspended for three days, and resumed on the fourth at the risk of losing the mail and the lives of those entrusted with its conveyance; when the navigation of the rivers was stopped, their banks strewed with fragments of houses, mills, &c; the highland roads washed into gullies, and the bridges in the low countries in many places washed away—at this period, so destructive to property, and when intercourse between various parts of the country was entirely stopped, it will be gratifying to stockholders to learn, that, with the exception of the sliding of the side of a bank on the road (avalanche) within two miles of Hamburg, the works have not sustained injury to the amount of five dollars. During this whole period the trips were performed regularly in the usual manner in the usual time and with the usual load, and the passengers experienced no inconvenience, except that resulting from a moist atmosphere. Had the system of embankments which is generally resorted to in such works, in order to preserve the grade over low grounds, been adopted for this work, it is probable that a large portion of it this day would have been a mass of ruins; as human sagacity would scarcely have anticipated the necessity of culverts sufficiently capacious to have afforded an outlet to such immense and overwhelming floods.”

But the security afforded under such circumstances as the foregoing is not the only benefit likely to be derived in a climate where deep and drifting snows threaten to interrupt, if not prevent, railway communication for several months in the year. So plainly essential to the success of a railway are certainty and regularity of communication, that without some satisfactory assurance that these are attainable at a limited and reasonable expense, the prudence of embarking in such an enterprise might be justly questioned. When, however, uninterrupted transportation may appear to be feasible in a plan not only avoiding extraordinary outlay, but requiring even less expense for the whole construction and management than by any other, its claims to consideration in these Colonies seems to be such as will be scarcely overlooked. Such plans appear to be that of an open wooden structure, elevated above the ordinary level of the snow, and providing slight obstruction to the same in a drifting state. There are questions of detail in relation to this object which may for the present be deferred.

After an eight years trial of their system, the President of the South Carolina Rail Road Company, in a report dated in 1840, thus speaks of its merits:–

“The superiority of the peculiar construction of our road – the superstructure on piles driven into the ground and embanked afterwards – was shewn very satisfactorily in the repairs after the great flood of the  Savannah River in May last, which raised the water five feet over top of the rails, yet not one fourth thus covered were removed; and had it not been for the great weight of the timber, houses and whole trees which were forced against it with great violence, no part would have been dislodged from its foundation.

“The plan regarded by many as a great mistake in the building of the road has proved an economical one, as well in repairs as original construction.”

The following is from a semi-annual Report in 1843:– “The construction of the Road on piles is becoming more in favor by others, as well as those having thee advantage of it. Several roads at the North are partially of this plan. The New York and Erie Railroad, to be 446 miles long, is to be about one half built in this way. Over 70 miles of piles have been already driven.

“It saves much of the cost of embanking a road by being able to transport the earth upon it to fill the valleys and swamps, and before it is necessary to do this, the income of the road is providing for the payment while it is constructing.

“It preserves the line and level of the road after the embankment is made. When roads are built on fills and cuts without piles, the superstructure is continually liable to be disturbed by the sinking of the banks, or water settling in the excavations, much to the injury of passing trains, breaking axles, and otherwise deranging the machinery of the engines.”

The same report furnishes a statement of the cost of the Road, from which it appears that, for the wooden structure and materials, it amounted to $584,542.43; or equal to $4,300 per mile, exclusive of iron and spikes for the plate rail, which amounted to $125,309.47, or about $921 per mile. Preliminary expenses, Surveys, Engineer department, workshops and materials, machinery, engines, cars, inclined plane, land, road police, office expenses, &c, amounted to $241,296.47; or equal say to $1,774 per mile.

The road continued in active operation as thus constructed until 1836 when heavy repairs became necessary. At this time, therefore, the whole expense of the construction of the road, exclusive of the Iron rail and the other expenses above enumerated, was no more than $4,300, or £1,075 Halifax currency, or about £896 sterling per mile; and including everything, only equal to about £1,460 stg. per mile, under the unfavorable circumstances of a first experiment.

Afterwards the replacing of such timber as had began to decay, the embanking of the piled portions of the road, and importing heavy flanged iron, increased the whole cost to $2,506,762.61, or equal to $18,432 per mile, up to the year 1839 since then the increase of cost appears to be upwards of one half more. But how this arises, or for what reasons the Company may have deemed it necessary or expedient so largely to increase their permanent expenditure, are questions which do not seem to be involved in that under consideration. It appears that during a period of at least four years the advantages of a railway were obtained and enjoyed for the small expenditure before stated; but afterwards that the progressive re-construction of the work, at heavy expense, became necessary. It is therefore chiefly desirable to ascertain whether the same advantages might not have been secured for a much longer, or even for an indefinite period, without further extraordinary expenditure, or any serious practical objection to the plan itself, had the material employed in the first construction been imperishable.

The opinion of Engineers of long-known ability and experience in the United States, as well as of others practically conversant with the subject of Railways is that there is no valid objection to a properly constructed wooden foundation, except the perishable nature of the material. That as a general rule, to which all must assent, the introduction of perishable materials into works intended to be permanent, is as much as possible to be avoided; and at the present time wherever the means can be commanded, earthwork and masonry are generally preferred. Under different circumstances, however, and where wood is abundant, the piling system is adopted, if the character of the country will permit; for besides being more rapidly executed, it is regarded as an efficient and economical foundation, even at the risk of a periodical renewal every five or six years.

In some of the substantially constructed Railways of New England, small portions founded wholly on wood are to be met with, and which have been so constructed either from the necessity of the case, or from some consideration of present economy. In passing over these the passenger is unconscious of any transition from the earthen foundation.

I was kindly invited to pass over and examine, in company with the Engineer a portion of wooden foundation adopted on a Branch Railway from Salem to Danvers, just completed and opened for traffic. It had been thus constructed with a view to dispatch and the more immediate benefit of the Railway, leaving the filling up with earthwork to future convenience before the wood should have time to decay. The elevation of the work, substantially constructed on piles, is from five to thirty feet above the natural surface of the ground. During the passage of the tram no vibration or unsteadiness was perceptible; and in standing upon the platform behind the last car, as it were in mid air, and in clear view of the open wooden framework below, retreating with a velocity of 25 miles per hour, It was not easy to conceive how it could be more difficult to pass any ordinary depth of our northern snow, and that at rates of speed equal to those attainable under the most favorable circumstances.

The expense of this wooden structure was from two dollars to six dollars per running foot of the railway. But besides the great elevation of the way, a large proportion of the piles were driven to a great depth and in deep water. At two dollars per foot, for which a portion of this example was made, the cost would be equal to about £2180 sterling per mile, the elevation being about 10 feet, and the piles driven to a depth of about 12 feet. The timber was here, however, comparatively expensive, being obtained from a distance, and as an article of merchandise.

I was favored in a very obliging manner with the opportunity of inspecting the result of a wooden structure on the New York and Erie Rail Road, which is of the broad gauge, and intended as one of the great trunk lines of the Lake and western trade. The portion of which I have reference is near its commencement, and consists of a viaduct 60 feet at its highest part above the bed of the valley over which it passes. Thirty feet of this height consists chiefly of an earthen embankment, and partly of a stone bridge; but in order to avoid the delay and immediate expense of so heavy an embankment as that which would be required for the whole elevation, the remaining 30 feet was filled up with strong trestle of white oak. At the time of my visit this had been subjected to a regular traffic of upwards of five years, and still remained strong, steady and sufficient. But in order to provide against the certain effects of gradual decay the whole structure was in progress of being embanked with earth to the level of the roadway. Earthen embankments had also been made on this diversion of the road whenever the timber structure had in the first instance been employed. But I was assured by the Engineer of the work that no practical or efficient objection existed to this kind of foundation, except that of the perishable nature of the material, and that notwithstanding this objection, where wood is abundant, the plan was the most easy and rapid of execution, as well as in the first instance the most economical, and in a climate where communication is liable to be impeded by snow, it was superior to any other that had been devised.

A large portion of the Line of the New York and Erie Rail Road, where the country is favorable, has been piled; but the financial difficulties of the company having caused a suspension of their works until recently, they will be deprived of much of the benefits of the wooden structure. It has been exposed to decay during several years, but will still afford the foundation of a railway, which besides sustaining regular traffic in the meantime, will facilitate the substitution of earthen embankments in an economical and expedient manner.

A practical exposition of the merits of this system is afforded by the following from the evidence of one of the intelligent and experienced Engineer of the New York and Erie Rail Road, as given before a Committee of the Legislative Assembly of the State of New York, appointed to investigate the affairs of the Company, in the year 1842:–

“Question 23 – Have you made or examined any tests with the view of ascertaining the comparative merits of a Rail Road constructed upon piles, and one upon a bed of earth or stone, and if so, state the conclusions to which you have arrived, with the facts connecting therewith?

“Answer – I have made numerous examinations relative to the construction of Rail Roads upon piles within the last three years, and have become thoroughly convinced that the piling system is an important improvement in Rail Road construction, and especially in northern climates, where severe frosts and deep snows are common in the winter months.

“A road resting upon white oak piles (from eleven to eighteen inches in diameter) driven to a depth of five feet or over, and in all cases reaching a solid foundation, and sawed off two or three feet above the surface of the earth, is not liable to derangement by frost, nor obstruction by snow, and combines in a greater degree than any other mode that has been adopted in this country, cheapness and permanency – the two most essential requisites in Rail Road construction. Piles that have stood in the most exposed situations on the Utica and Syracuse Rail Road for the four past winters, and those driven on this division during the summer and fall of 1840, in every variety of soil, abundantly prove the fact that frost cannot displace them, if they are driven to a depth of five feet or over.

“A piled road is also free from the obstructions and dangers incident to a graded (earthen) road, in consequence of the washing of the banks by floods and rain, and by settling when on a soft bottom; thereby requiring constant annual expense to adjust the road and replace the earth material.

“It will, I think, also lessen if not entirely prevent the frequent accidents that occur on graded (earthen) Rail Roads, arising from cattle and other animals obstructing the track when trains are passing at high rates of speed.

“The permanent and uniform foundation that a piled road affords during all seasons of the year, cannot, I think, be too highly appreciated; and for roads calculated to transport heavy freight, its decided superiority over the usual modes of constructing Rail Roads in the State cannot be questioned.

“From the experience afforded me during the construction of the Syracuse and Utica Rail Road, as well as the two past years on this division, I have no hesitation in strongly recommending the adoption of a piled road, wherever the nature of the soil, surface of the country, and a supply of suitable timber will admit of the structure. On this division there is being made over one hundred miles of piled road, along the valleys of the Susquehanna, Chemung, Tioga, and Canisteo rivers, of which the piles are now driven for seventy miles; and the eight steam pile-drivers are now in operation, driving the residue at the rate of ten miles per month.

“The actual cost of this piling (when sawed off in readiness to receive the superstructure) has averaged less than two thousand dollars per mile including the white oak pile timber, from eight to thirty feet in length, and from eleven to twenty inches in diameter, costing on an average about three and one half cents per lineal foot, delivered on the line of road. These piles are driven from five to twenty feet, and where required by the looseness or softness of the earth, double piles are driven to the depth of fifty feet or more, and sawed off from two to four feet above the embankment, or the natural surface of the ground.

“To have substituted a graded (earthen) road-bed in place of this piled road in this division would have cost not less than four thousand dollars per mile for the whole distance, without including the grading necessary for the piled road, when the surface of the earth requires to be excavated or embanked for the purpose of bringing the earth grade from one to four feet from the grade-line of the road. No difficulty has been experienced in driving white oak, chestnut, or Norway pine piles below the reach of the frost, in sand, gravel, clay, or alluvial soils; and wherever excavations or embankments occur exceeding four feet in depth or height, the cost of removing the additional quantity of earth necessary for a graded road-bed, with its side ditches, exceeds the cost of piling, including the piling timber.

“The excavations for piled road on this division are made twelve feet wide on the bottom, with side slopes of one foot vertical to one and a half feet horizontal. The piles are sawed off one foot above the bottom of the cut, and a ditch of three feet wide and one foot deep is made between the rows of piles, to carry off the water. The earth from the excavations is carried into embankments, where the grade exceeds three feet in height. The embankments are made to within three feet of the tops of the piles, twelve feet wide on the top, with side-slopes of one and a-half feet to one foot.

“From the experience that I have had in the construction of pile road, and from the examinations that I have made relative to the cost of grading, and keeping in repair the ordinary graded roads of the country, I think I am within bounds when I say that the interest of the amount saved by building a piled road instead of a graded road, for the one hundred miles on this division, together with the annual expense in keeping a graded road-bed in good adjustment and repair, will renew the piles, should it be necessary, every five or six years, so long as suitable timber can be obtained at twice its present cost in that division.

“If the white oak piles should not remain sound more than eight or ten years, the expense of filling around them with earth, at the expiration of that time, with the use of cars to move the earth, would cost at least fifty per cent, less than it would now cost to make the embankments to the graded line with barrows or wagons; as most of the earth would require to be drawn from the hills for great distances, in consequence of the alluvial soil, found along the bottom lands of the rivers, not being suitable for a road bed for a graded road. Wherever the valleys to be filled are deep, and the excavations from which the earth is to be taken to embank over them, are at any considerable distance off, the hauling of the earth is postponed until the track is laid on the piles, and then done with cars at a great saving of expense.

“Another consideration in favor of a piled road is, that when the piles are partially decayed, the earth embankments can be cheaply brought up to grade, as has been shewn, and the strength of the pile will, for many years thereafter, keep the road from settling; thus you will perceive that the superstructure having been kept from the ground, and of course in a great measure preserved, the earth being brought to grade, as before remarked, and well rammed under the superstructure, we have a new and permanent road, much more permanent than roads where the rail is laid upon a new, and of course not thoroughly settled embankment.

“The construction of pile road on this division has, I think, enabled the company to make contracts with the landholders along the route (where such road is made) for right of way, fencing and farm-crossings, for at least seventy five per cent less than they could have done had a graded road been substituted in its place. This arises from the fact that while the piles remain in good preservation, there will be no necessity of fencing along the railroad, excepting the nailing of a few boards upon the piles, while the farmer can cultivate all the land sold to the Company, and which is from 4-1/2 to 6 rods in width, (until it is required for a graded road,) except the width of eight feet, occupied by the piles The piled road also permits cattle and other animals to pass under the track, and thus saves the great expense usually required on graded roads, to make embankments on the roads for farm crossings, or expensive bridges or culverts, to allow teams and cattle to pass under the road. A large amount is also saved in the single item of cattle guards, necessary on graded roads, to prevent cattle from passing from private or public roads, on to the track of the railway, and thereby obstructing the passage of trains; and which occasions a great share of the destruction of life and property on graded roads.

“As I have before remarked, the great advantages of the piling system consist in its cheapness and permanency; and in regard to its durability, it will be seen, that if the perishable material of which it is constructed can be renewed at an expense of less than the interest upon the difference of the first cost, and necessary annual expenses, (when compared with a graded Road) it must result in an ultimate saving of expense.”

The substance of this testimony, received with that consideration to which the opinions and experience of other competent Engineers support its claim, gives to the question of Wooden Railways a peculiar interest in these Provinces, and places in a striking light the importance of some available method of insuring their durability after their first construction.

The most satisfactory experiments which as yet appear to have been made in the preservation of wood, are by the process of “Kyanizing;” not that they conclusively establish the comparative merits of this process, but because they extend over a longer period of time, say than any experiments by the more recent methods which have been introduced to public notice, amongst which the most approved appears to be that of “Paynizing.”

No well authenticated instance is known of the failure in the United States of Kyan process where it has been fairly tried. On the contrary, prepared Railway sleepers of Spruce, one of the most perishable of American woods, exposed in a manner least favorable to its durability, have been found at the end of six years, the full time of its ordinary duration, remaining quite sound and elastic, and even retaining the original marks of the saw. The cost of this process by hydraulic pressure has been found to be 5 12-100 cents, or about equal to 3 1- 8d Halifax currency per cubic foot. By soaking only, it ought to be much less, as the value of the corrosive sublimate necessary to each cubic foot, does not, according to some experiments, exceed 1-1/2d currency. The efficiency and economy of this process, as now confirmed by numerous experiments, has tended to create a general confidence and renewed interest in it; the risk of further trials is now freely incurred, and its extensive adoption is highly probable.

The simple process of natural absorption, by immersing the foot of a newly felled tree in a preservative solution, say the pyrolignite of iron, seems well deserving of consideration and further experiment. By this process it would appear that the vitality remaining in the wood for a short time after it has been cut, causes the artificial fluid to circulate with the natural sap throughout the whole tree. Mr. Bethell claims a right in this process by patent, dated July 11th, 1838. Public attention was drawn to the discovery by Dr. Boucherie, of Paris, in 1840. It would of course be necessary that this process should be practised on the spot where the timber is cut.

It seems difficult to attach too much importance in these Provinces to some feasible and certain method of rendering wood, if not imperishable, at least capable of resisting decay for a long period. The effect would be to place us in a position to prosecute a railway system, and other works, at a cost so moderate as to remove reasonable fears of success. It would probably also give us a large share of additional manufacturing benefit in the staple of the country. For the preservative process seems to be most easy and effectual when applied whilst the wood is in a green state.

Wood as a Substitute for Iron Rails

So far we have chiefly considered the eligibility of wood as the principal material in railway foundations. The entire substitution of wooden for iron rails, and thereby avoiding nearly the whole expense of the latter, has perhaps engaged more attention in these Provinces than in the United States. On first naming the subject of wooden rails in that country, you are understood to mean the wooden rail, or longitudinal sill, upon which a light plate of iron is laid and secured as in the first experiment there. But this expedient having been found to be very objectionable and insufficient, especially under heavy locomotives and high velocities, it is generally becoming abandoned in favor of the heavy iron rail. The light iron plate of 2-1/2 inches by 3/4 inch is found to be too flexible, and the wood beneath it too compressible. It is now deemed necessary, even with a continuous wooden bearing, that the rail should possess the stiffness of the usual forms of heavy iron rail. The failure of the light plate rail, therefore, seems to have created a degree of prejudice against much dependence upon wood, and a dependence upon it altogether is regarded as somewhat chimerical. The results of limited experiments in England have not apparently had the effect of disturbing in the United States the general conviction of the necessity of employing strong rails of iron in order to sustain a heavy transportation.

It may be allowed that the statement of the experiments as yet made, though calculated to give a favorable impression, do not settle the question of the safe application of the wooden rail to the various circumstances of a long line of railway intended to sustain heavy loads and high velocities. Enough however has been made known to draw the attention of these Colonies to the importance of a more perfect investigation of the subject. A few suggestions in relation to it I will venture to submit.

The principle of the wooden rail is acknowledged to be without novelty. Its employment is merely a return to what was in use upwards of two hundred years ago, but now resumed under the more favorable circumstances of greatly advanced knowledge and experience. The form of the rail appears to have been not materially different from that which has been subjected to recent experiments; but the wheels of the wagons are said to have been, during a long period, only of wood, and of rude construction. Afterwards, cast iron wheels were introduced, which, it would appear, from their imperfect adaptation to a rail of much softer material, soon led to the use of cast iron rails. Again a difficulty was experienced. It was found that the cast iron rails, especially when their surfaces were narrow, cut the rims of the iron wheels, forming indented grooves, which caused considerable friction and the frequent breaking of the rails. To remedy this, the breadth of the surface of the rail was increased, which diminished the evil to a certain extent, but the expense of repairs was still considerable. A complete remedy was eventually effected by “case hardening” the rim of the wheels in the process of casting. The further development of introducing malleable iron rails, was for several years retarded by the same evil which first appeared in the use of cast iron rail; the narrowness of the edge being found to cut the periphery of the wheels. The cast iron rail with a broader surface was therefore preferred, because a malleable iron rail with a surface sufficiently broad was too costly. But eventually a malleable iron rail was produced, the section of which presented the same bearing surface as the cast iron rail, combining with lightness the necessary degree of strength.

Now it seems manifest that these progressive improvements proceeded from a necessary regard to the relative hardness of the periphery of the wheel and the bearing surface of the rail. Cast iron wheels were found to cut a soft material like wood, and rendering cast iron rails apparently necessary. But these, when narrow, were found to return to the cut wheels, an evil which was in part remedied by making the surface of the wheel harder. It was also found necessary to the success of the malleable iron rail that the breadth of bearing surface should be adjusted to the relative hardness of the periphery of the wheel.

These considerations seem applicable to the failure of the iron plate rail spiked upon a rail of wood, as tried in the United States. It is obvious that a thin ribbon of iron, only 2-1/2 inches wide, could do no more than protect the wood from the abrasive action of the wheels. It was too narrow and flexible to prevent the effects of compression. Hence, nearly the same result might be expected, though in a less rapid and sensible degree, as from the first experiments of narrow cast iron wheels running immediately upon wood. A thin strip of iron, subjected to the rolling action of a heavy pressure, and depending for its stiffness upon a soft and irregularly compressible bearing, must necessarily lose the .essential qualities of a rail. It could not remain either uniformly plain or rigid.

For this evil there appears to be three remedies, differing materially in their relative economy.

  1. An iron plate rail widened to an extent to be determined by its increased stiffness, and the hardness of its wooden bearing.
  2. An iron rail of suitable form, and sufficiently stiff to compensate for its narrowness of bearing upon wood.
  3. A rail exclusively of wood, to which the width of the rim of the wheels of the locomotive and of the train shall be duly adjusted.

The second of these remedies is that adopted in the United States, and which involves a minimum of expense of eight or nine thousand dollars per mile for the iron and its fastenings.

Yet without further and satisfactory experiments there seems to be no sufficient reason to doubt that nearly the whole of this outlay-might be avoided by the third proposed remedy; and which is the adoption of a duly proportioned wooden rail, to be acted upon by iron wheels, the peripheries of which shall be plain, and of a width which shall be adjusted to the weights and velocities to be sustained and the relative hardness of the wood, thereby obviating the necessity of a bearing surface of metal in any form. But the experiment should include the substitution for the “flanches” [sic.] now in use, either the grooved diagonal guide wheels of Mr. Prosser, or plain horizontal wheels to roll against the inner side of the rail, for the same purpose.

I would therefore suggest, in order more perfectly to test the merits of this kind of rail, that such experiments should be made as may be sufficient to determine whether its efficiency does not depend upon a due adjustment; of the width of the iron periphery of the wheel as may be due to the relative hardness of the wood under the pressure of given loads, and under the least favorable circumstances incident to railway transportation. It is probable that one result of such experiments would be to show that the diminution of the compression is nearly as the square of the ratio of the increase of the width of the periphery of the wheel, that is to say by increasing such width twice, thrice, or four times, we relieve the fibres of the rail from the compressing or crushing effect as four, nine, or sixteen times.

Further experiments appear also to be necessary in order to determine the adhesion of the driving wheel upon wood under various circumstances. It has been represented as much more than upon iron. In a dry state this is very probable; but in a perfectly wet state it is doubtful whether it will not be considerably less, and if so, the supposed advantage of being able to ascend steeper acclivities on the wooden rail may cause disappointments against which it is very material to guard. The same expedient, however, which has been beneficially adopted in the iron rail in a wet state, that of sanding, may prove to be equally or more efficacious on wood.

In the meantime there appears to be no sufficient reason to discourage a reliance upon wooden rail under ordinary circumstances, if abundant breadth be given to the rims of the iron wheels. In the breadth of the wood a liberality can be observed, which in the use of iron is restrained to a minimum by its costliness.

In closing these imperfect observations, it may be proper, with regard to the general recommendations which they convey of wooden foundations for railways, to remark that it is not pretended that they can always obviate expensive cuttings and embankments, which must in some instances of necessity be encountered.

I have the honor to be, Sir,

Your Excellency’s most obedient humble servant,

J. WILKINSON.

To His Excellency Sir Wm. M.G. Colebrooke, &c, &c, &c.

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Written by johnwood1946

July 31, 2013 at 9:29 AM

Posted in Uncategorized

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