The following is a practicable table of the power of traction of locomotive engines upon railways, exhibiting the gross load in tons, including the tender, at different rates of speed, and upon inclinations varying from a level to an ascent of one hundred feet per mile, deduced from the formula of De Pambour, one of the ablest writers on the subject.

Weight of engine, 13 tons; evaporating power, 55 cubic feet; cylinder 1.16 feet diameter.

Total pressure of steam to the square inch in the boiler, 70 lbs.; diameter of driving wheels, 4' 5; length of stroke in feet, 1' 33"; friction of engine, 14 lbs. per ton; friction of carriages, and additional friction upon engine from load drawn, 8 lbs. per ton. The ton employed equals 2000 lbs.; the wheels of the engines are supposed to be coupled, if necessary,

when drawing the maximum load, or otherwise so arranged as to bring the weight of the tender upon the driving wheels.

Weight of Engine, 10 tons; evaporating power, 42 cubic feet; cylinder 1 foot diameter.

There was a trial line of a level run from the State line in Shelburne, to the summit level in New Hampshire, near Bowman's tavern in Randolph, to ascertain the practicability of carrying the road across the White mountain range, which there has a direction at almost right angles to the line of the survey. The summit was found to be elevated 7985 feet above the termination of the line in Shelburne, and 1,4728% feet above high water mark. On arriving at the summit we were met by a number of gentlemen from Lancaster, who feeling a deep interest in the proposed work, desired that the

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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 836907 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, 440 feet; and the distance from the summit to the Connecticut river at Lancaster bridge, 15 miles; making the average grade 42 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 superstruc ture of the road out of its proper position.

The superstructure recommended is that described in the former Report. I have also made an esti

mate, 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,

Clay, gravel and some ledge,

Sand, gravel and loose rock,

Granite loose rock, clay and portions 10 of ledge,

Ledge, loose rock, gravel and sand,

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78 miles.