« PreviousContinue »
We shall further premise, that twelve feet for the embankments (the width ordered) is too narrow for safety at all times, and too narrow to admit of being worked without great loss of time. We shall assume 16 feet as the least admissible width, even for the narrow track.
Taking Sections 10, 11, 12 and 13, embracing about 4 miles of the road, we shall exhibit the gross amount of cutting and filling upon each, with the cost of the same at the prices at which the contracts are made—both for double and single track.
Width track. Cutting.
Cost. Difference. 20 and 16. 33684.7 yds. 42729.7 yds. 9827.67 2798.18 26 and 26. 39209. 54895. 12625.85lor 23 per cent.
20 and 16. 152772. yds. 159801. yds. 20930.35 3765.67 26 and 26. 60472. 70560. |24696. or 15 per cent.
SECTIONS 12 AND 13.
20 and 16. |172755. yds (183641. yds.89984.096945.91 26 and 26. (194400. “ 215400. 96930.00
per cent. *
The average of the difference in cost, as above, is about 15 per cent. We shall assume što š as the additional cost of grading the road for a double track throughout the division. The total difference upon this hypothesis, for the 191 miles will be about 75,000 dollars ; upon the supposition also of all the excavations being earth, and earth and loose rock, in the proportions estimated in the four above named section In the case of a rock cut, there being but an inconsiderable slope to be given to the sides, the expense of the cuts would be nearly in the ratio of the widths, or 26 : 20, say 23 per cent.
* In consequence of some modifications made in the grades of the line across the summit, the amount of cutting and filling as stated in the above table is less than the quantity furnished by the final computations upon the established line. This does not affect the principle, however. The comparative results are all which we are desirous of presenting to your notice at this time.
The contractors in their proposals for executing the work, have made a difference in favor of the double track, of from one to four cents per yard for earth, from 21 to 10 cents for loose rock, and from 5 to 30 cents for solid rock.
It remains to us now to state such objections to the width (as at present ordered) as appear to us obvious. They may be thus summarily enumerated.
i. The difficulty and disadvantage of working any amount of force either in the cuts, or upon the embankments, particularly the latter, 12 feet in width not allowing sufficient space for the carts to turn or pass each other without liability to accident, the carts being 6 feet at the axles, and the embankment but 12 feet, the consequence in the manner referred to is obvious. We may add in this place the proof of this by stating that even now, the carts upon the only embankment which is carried out, have been precipitated some half dozen times while turning or passing each other.
2. The embankments being constructed, and in places rising from 20 to 60 feet in height, with a surface width of 12 feet only, what might we expect their condition to be at the end of a season-affected as they must be by the action of the frost, and washed into gullies by heavy rains ? They might, by the effect of single storm, be rendered impassable.
3: In the event of an accident to a train of cars upon an embankment, by which they should be thrown off the rails, some space is necessary to work, in order to replace them upon the track; and while this may probably be done if they are not broken, what is the alternative if they are, say a wheel ?-there is no room upon ithe side of the track for them to remain for another train to pass, but must effectually stop the passage of every thing, until they can be removed from the bank, by being lowered perhaps into a swamp or ravine, from which it may be equally or more difficult to get them again upon firm ground.
4. It has been said that if these difficulties occur, and the narrow bed is proved to be too inconvenient, that the track may, at any subsequent period, be widened, and at a less expense, even, than in making it sufficiently wide for a double track in the first instance. The great difficulty, and
we might say impracticability of this proceeding, is too evident to any one having the least knowledge of the matter, to require an answer. We might take for an example the rock cut on the Worcester Rail Road, and ask, in increasing the width of the track at that place, what might and probably would be the effect of a single blast? It requires but little reflection to answer, that the road might, at any moment be rendered impassable, and in such a manner, that all the force within the control of man could not remove the obstacle in 24 hours. The road being graded for a single track, the rails of course would be laid in the middle of the graded surface; the whole would of necessity have to be taken up before the second track could be laid, and therefore the case is very different from that in which the road is prepared for two tracks in the first instance.
5. The difficulty of forming a new embankment against an old one, (such as would be required in the widening of the road bed,) is not to be overlooked. A writer
A writer upon this subject says, “ It may be proper to advise that new banks ought not to be placed upon steep ground without considerable care in first forming it into levels, like steps, to prevent the slipping of the new part, as happened near Bradford on the Kennet and Avon canal; after all the care that was taken, great lengths of the canal slid down into the Avon river below.”
From the foregoing statements, the conclusions which we arrive at are these :
First, That it appears to us that sound policy would dictate the propriety of grading the road sufficiently wide for two tracks, even upon the supposition that but one is to be laid down. In fact the width usually assumed for two tracks, is scarcely more than is requisite for one, to insure proper drainage, and to clear the road bed of snow.
Second. If it should be deemed expedient by the Board to adhere to the resolution of the 4th October, directing the road to be graded for a single track, we would state the necessity of extending the width of the embankments to 16 feet upon all parts of the road : that upon the 12th and 13th Sections, embracing the summit, and where both cutting and filling are heavier than upon any other portion of the line, the road be graded for two tracks, the cuts to be widened for an opportunity to drain the bed thoroughly,
and the embankments to be extended, for safety. The difference in cost, at the prices agreed upon with the contractors, as is stated in the table above, is $6945 91, or only about 8 per cent. additional, and this upon a length of road of about 2 miles. The difference in price between a double and single track, being upon these sections 4 cents per yard for earth and loose rock together, and 10 cents for solid rock. Third. We would respectfully suggest, for your
consideration, the propriety of modifying the order of the Board in reference to the width of the track, in such a manner, that your engineers be invested with discretionary authority to alter the width of the cuttings and fillings at such points of the road as may seem to them judicious and proper, according to the circumstances of the case. A single fact will serve to show the necessity of this measure. cases the embankment exceeds the excavation; to make up the deficiency, the obvious course would be to widen the cut sufficiently to form the embankment, in preference to borrowing earth elsewhere. This is a single instance, but it will convey an idea of the inexpediency of defining too closely these matters of detail; they are in most instances contingent in their nature, and require to be arranged and suited to each particular case.
We omit all reasoning on this part of the Report, which we think might, with propriety, be based on the eventual responsibilities of your Engineers for whatever strictly pertains to their profession.
WM. GIBBS MCNEILL,
SURVEYS BETWEEN SEVEN MILE RIVER IN BROOKFIELD,
AND TEKOA MOUNTAIN IN MONTGOMERY.
Worcester, Jan. 15th, 1837. TO THE PRESIDENT AND DIRECTORS OF THE WESTERN
RAIL ROAD CORPORATION. GENTLEMEN,
The Reports which were made to the Board on the 15th of August, and 30th of September last, contained a description in detail, of the several routes which were surveyed and approximately located, between the villages of Worcester and East Brookfield, and the order of the Board of the 4th October, confirming the location recommended by the Engineers, in their Reports above referred to, established that portion of the line. It becomes our duty, now, to lay before you a statement of the operations of the Engineer department since the Report of 30th September was adopted by the Board.
Immediately subsequent to that period, the requisite measures were taken for the definitive location of the route between Worcester and East Brookfield, comprising the first division of the road, and on the 19th of October, this portion, embracing an extent of 19.5 miles, was advertised for contract. Proposals were invited until the 20th November, and propositions from a large number of efficient and experienced contractors were received. Upon such of the sections as the proposals appeared to be suitable, and advantageous to the Corporation, decisions were made, and the work was let; while upon others, embracing portions of the work of greatest magnitude, the decisions were deferred, to afford full time to the contractors to acquaint