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a point opposite the great falls, distant 8 miles 2360 feet, with an elevation of 221 feet; from thence it extends to near Boody's tavern in Windham, where it intersects the first line, which is distant from Portland by this line, 18 miles 3210 feet, and has an elevation of 2970 feet; but by the first line the distance to the same point is only 17 miles 424 feet, making a difference in its favor of 4250 feet.

As to which of these lines the preference should be given, is a question which cannot be satisfactorily determined at this time, and may with propriety be left for consideration until the time arrives for making the definite location, when all such facts as relate to the peculiar advantages of each route, will have been carefully collected, and thus render a solution not only less difficult, but more correct than can possibly be made from the incomplete data which are now afforded; but so far as I am able to determine, from the examinations which have been made, and the elements which have been obtained, the first line appears to be the most eligible, it being the shortest, the least curved, has fewer and less elevated acclivities, and admits of the construction of a Railway, at a diminished expense; besides it would pass sufficiently near the river, at several points, to accommodate some of the sites for mills and factories; but still it is possible that there are advantages to be secured from the establishment of the second line,

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which may more than balance those which have been suggested as pertaining to the first.

As to the general direction of the whole line which has been surveyed, although unwearied pains were taken to ascertain the most favorable route, it is not improbable that deviations could be made, by which the extent and number of the curves might be diminished, at some points, and the grades rendered less abrupt in others ; for, in running an experimental line, for such a distance, through a country chiefly covered with a dense forest, and whose surface is so broken into steep hills and irregular valleys, it is impossible to determine, whether the best line has been obtained, by such preliminary surveys and explorations as have now been completed, that could be selected, after repeated examinations of the topographical features of the adjacent region, on both sides of the delineated ronte, shall have been made. Still it is believed that the extent of straight line compared with the curved, is greater than is usually obtained in trial surveys of equal distance, through the New England States, there being 58 miles 1004 feet of the former on the main route, and but 19 miles 4280 feet of the latter. The maximum cur. vature has a radics of 900 feet, and that for a distance of only 400 feet, while the remainder have a radius of from 1146 to 11460 feet. The total amount of lines of deflection are 17 miles 1526 feet,

of which 13 miles 1460 feet are straight, leaving only 4 miles 66 feet of curved line. For statement of straight and curved lines, see tables in appendix.

The grades have been arranged so that they shall, as much as possible, be descending towards Portland, believing that the preponderance of transportation will be in that direction. The maximum grade is 48 feet per mile, which, in comparison with those on other Rail Roads, taking into consideration the improvements which have been made in locomotive engines, are not considered so objectionable as formerly, to the attainment of high rates of speed, or the transportation of heavy trains of merchandize. I have given in the annexed table, the grades of the main line, and the length of each, in their respective order.

. otal Length or Denomina rise &

Plane in tion. fall of Ratio feet

Palie.

Tola! Grade Length or Denomina- rise & per

Plantilla tion. flot Ratio niile, feet.

plane

Grade

per mile.

60546

112'2

32

1 820

1 48307

1 860

14,400 Ascent

22 12,200 Descent 70 1.30.29 18,000 Level

9,000 Ascent 8 4.71 31,200 Ascent 150 2 25.38 6,000 Do.

187.5

28.06) 16,400 Do.

20 6.44 14,000 Level 12,200 Do, 70, 114., 30.294,200 Ascent 20 to 25.14 17,000 Do. 35 10.66 8,400 Level 8,600 Descent 40 zis 24.55 16,400 Ascent 70 , 22.10! 14,600 Level

17,200 Do.

20

6.14 4,800 Ascent 40 130 44 12,200 Do.

21.72 12,000 Do.

110

48.40/10,200 Do. 20 10.36 21,600 Do. 40 10.73 16,200 Level 14,800 Do. 65 26.04| 9,600 Ascent

.22 21,400 Descent 50 12.31|28,200 Descent 10 1.87

Average grade per mile for the whole length, viz: 78 miles 8 feet and 39.

50 ?

244

1659

510

1 2276 1

40' 1

240

2720

The following is a practicable table of the power of traction of locomotive engines upon railways, exhibiting the gross load

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.

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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.

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19

7
6

Level. | 277 230 175 137 108 85 67 52 40

10 177 148 113 87 68 53 41 32 23 20 129 106

47 37 28 20 14 30 100 82 63 47 36 23 20 14

10 40 81 67 50 37 28 21 15 10 6 50 70 55 40 30 22 16 11 7 60 60 48 35

26

19 13 9 70 51 41 29 21 15 11 80 45 36 25

13 9 90 40 32 23

11 100 35 29 21 14 9

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 summit was found to be elevated 798.500 feet above the termination of the line in Shelburne, and 1,4721017 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

the survey.

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