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level might be continued to the Connecticut river at Lancaster bridge, which was accordingly done, and the river at that point found to be 630 500 feet below the summit, and 836 907 feet above high water mark, The estimated distance from the line in Maine to the summit in New Hampshire, is 18 miles, making the average grade per mile, 41% feet; and the distance from the summit to the Connecticut river at Lancaster bridge, 15 miles; making the average grade 428 feet per mile; so that it is confidently believed that the line could be located with a maximum grade of 50 or 60 feet per mile, which is much less than those on some parts of the western road of Massachusetts; and not so steep but that locomotive engines can be used with perfect ease and safety; for the engines now made are capable of ascending much steeper declivities than formerly. From the great perfection which has been reached in the construction of locomotive engines, and the accuracy under ordinary circumstances, with which their time of transit, and the arrival of the various trains at the several turnouts and depots, can be timed, it is believed that a single track, with a proper number of turnouts, would not only be sufficient, for all the transportation on this route for a very considerable period, but would very much diminish the cost of construction.
This plan has been adopted on the Rail Roads from Worcester to the New York line, and those from Boston to Portsmouth, and from the Lowell road to Exeter. The estimates, therefore, for this route, have been based upon a single track with a road bed sixteen feet wide; the slopes to be one and a half feet horizontal to one foot perpendicular rise, except in rock formation, where the cut can be nearly perpendicular.
It is respectfully, yet urgently recommended, that the Rail Road should pass, either sufficiently high over, or so deeply under all other roads, as to give to the travel of each a free and uninterrupted passage. This will effectually prevent those numerous and disastrous accidents, which are so unavoidable, where the intersections of the rail and common road, are on the same level, as has been illustrated where every possible precaution has been taken, to prevent collisions and other fatal consequences.
The grade line of the road has been laid high, as it is now considered absolutely necessary to do this, in sections of the country subject to such severe and deep snows as the portion of the State through which this line runs, to prevent the obstructions that would otherwise occur, and also to give the road a good drainage, so that the road bed shall not be saturated with water in the fall, and having no chance to escape, freeze, and throw the superstructure of the road out of its proper position.
The superstructure recommended is that described in the former Report. I have also made an estimate, based upon an iron plate rail for superstructure, two and a half inches wide, and three fourths of an inch thick, laid on longitudinal sills of wood, eight inches square, and secured to them by spikes or bolts. The sills to be placed on sleepers or cross ties seven inches square and arranged three feet apart from centre to centre. But it is proper to state that I do not recommend this mode of construction; for although it is much cheaper in the first instance, it is not so durable, requiring frequent repairs, and the engines would not be able to perform the same amount of work, as on a road of the construction first named.
The abutments and piers of the bridges, and the culverts to be built of stone, but not laid in mortar. The stone materials required for the construction of the piers and abutments, and timber for the bridges, sills and sleepers of the road, can be obtained, of a superior quality, near to, and throughout nearly the whole extent of the route, at a cheap rate.
Commencing at Portland, the excavations will principally be made through, and the embankments composed of, the following geological formations : Sand and loose rock,
2 miles. Clay, gravel and some ledge,
8 Sand, gravel and loose rock,
8 Granite loose rock, clay and portions
10 of ledge, Ledge, loose rock, gravel and sand, 42
The ledge cutting is principally through granite and mica slate, but there are portions of the route where green stone and trap rock occur.
. The estimated cost of one mile of superstructure of a single track and of H rail, is as follows: 1. H Rail 86 1-2 tons, 55 lbs. per yard, at $70 per ton,
6,055 2. 704 cast iron chairs or splicing plates, at 50 cts., 352 3. 616 lbs. of spikes, at 6 cts. per Ib.,
36 96 4. 29500 feet of hemlock long sills 8 by 3, at 11cts, 324 50 5. 1760 white cedar sleepers, at 20 cts. each,
352 Laying rails, including digging trenches, notch
ing and straitening rails, at $2 50 per run-
$7,920 46 Cost of one mile of superstructure of plate Rail Road,
$5,230 00 The line having been divided into sections, for the purpose of equalizing the excavations and embankments as much as possible, the following estimate has been made of the expense of grading, bridging, clearing, and the superstructure of the road, exclusive of the right of way, offices, engines, &c., as they more properly belong to the report on the location of the line.
SECTION No. 1.
Distance, 6 miles 720 feet.
xcavation, at 75 cts.,
40 50 4,677 8,532 16 6,821 60 53,659 50 5,592
Total cost of grading section No. 1,
SECTION No. 2.
Distance, 6 miles 4,560 feet.
70 2,304 81,214 20 7,794 1,230 4,661
Total cost of grading section No. 2.
SECTION No. 3,
Distance, 5 miles 5,200 feet. 8 acres of clearing, at $18,
144 2 acres of grubbing, at $100,
200 21,745 cubic yards of earth excavation, at 20 cts.. 4,349 280,844 cubic yards of earth excavation, at 13 1-2 cts.,
37,913 94 400,967 cubic yards of embankment, at 14 cts,
56,135 38 50 feet of bridging, every thing included,
2,915 1,044 cubic yards of masonry for culverts,
2,088 5 road bridges, every thing included,
3,695 3 farm crossings, at $35,
105 Total cost of grading section No. 3,