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amount for different velocities. A certain velocity is necessary to generate steam; of course this velocity would be attained in the descents; but evidently it would be unsafe to give the engine such a load as might reduce the speed on the ascents below that which would be required to produce steam.

To one who has travelled upon roads with steep grades, the truth of this remark must be known-he must have occasionally witnessed the entire stoppage of the train.

After giving to the subject the mature consideration which its importance demands, we are fully of the opinion, that nothing has been developed by the recent surveys, which justify us in changing the opinion we expressed in the last Report, and we now respectfully reiterate that we consider the route by Morey summit entitled to your preference, and accordingly recommend that it be adopted.

The accompanying Tables (A. and B.) contain a synopsis of routes 13, 14, and 15, referred to in the above Report. They exhibit every detail, necessary for a comparative view of the several routes. The former contains the length, grade, excavation, embankment, cost, &c. of each. The latter contains the length of each curve, with the length of the corresponding radius.





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149 15411432.5 500 7162 9551041.8 1146 1432.5 1637 1910 2292|2865 5820 5730 1100 844 853 1041.8 900 191 199 5730. 800 31 2292. 500 456 465 1910. 900 866 897 1432.5 3100 205 209 2865. 400 70 83 2865. 1500 473 480 2865. 700 898 902 1432.5 400 215 221 1910. 600 103 112 3820. 900 609 612 1637. 300 905 920 1432.5 1800 225 232 1432.5 800 155 167 5730.1200 626 632 2292. 600 932 951 2865. 1900 190 198 2865. 800 661 668 1432.5 700 No. 15. By Inclined Plane, 296 308 5730. 1200 680 687 2865. 700 No. 14. By Henshaw Ridge 757 7621910. 323 328 5730. 500 762 766 1146. 400 15 2515730. 1000 797 816 1041.8 1900 .328 339 1910. 1100 771 784 716.2 1300 61 64 1432.5 300 856 869 1432.5 1300 800 796 802 955. 600 69 1432.5 400 896 903 1432.5 700 800 803 812 1146. 132 1432.5 600 932 951 2865. 1900

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Worcester, December 20th, 1836.



Your communication of the 12th November, calling upon the Engineers and Resident Engineer, for an opinion upon the expediency of constructing the First Division of the Western Rail Road for a single track was duly received.

It was intended to postpone a reply to this communication until the Report for the January meeting of the Board was prepared, and to state in it, fully, the disadvantages, which we conceived would arise if the order of the Board of 4th October, directing the road to be graded for a single track were adhered to, but upon further reflection, we have considered it our duty to anticipate the period of the Directors' meeting, in order that sufficient time may be afforded for the members of the Board to consider the reasons, which we deem it proper to offer against the proposed width for the track.

The order specifies that the cuttings shall be from 14 to 20 feet in width, and the embankments 12 feet at the surface.

We propose in the first instance to consider the subject in respect of the cost alone, intimating, respectfully, at the same time, that in our opinion the question should be treated independently of cost, upon the ground that the road should be graded for a double track, even if it be not intended to lay down more than the single track-and this for the reasons which we shall assign in their place.

The road being graded for a single track, the rails of course would be laid upon the middle of the bed, and not upon the side, as in the case of a bed for a double track; this being the case, we shall assume that the road bridges and stream bridges are to be of a width sufficient for two tracks, for the well known reason, that the expense of removing the wing walls, for the purpose of widening the abutments hereafter, would be greater than the cost of making them the full width in the first instance. The culverts we may make conformable with the width of the embankments, as they may be extended for a double track at any subsequent period without much additional expense. We shall further state that the maximum width authorized for the cuts (20 feet,) is barely sufficient to afford space for the ditches necessary to drain the road.

Upon these premises, we proceed to exhibit the difference in cost between the double and single track.

In level cutting, when the depth of the cutting (or filling) amounts to the width of the surface of the road, the areas of the sections of the slopes become equal to that of the bed. The cost in that case, therefore, of the bed and of the slopes will be equal. If the depth of cutting be greater than two thirds the width of the surface of the road bed, the ratio of expense is a decreasing one. If the cutting be less than 2, the converse is true. Take, for an example, two widths, say 15 and 30 feet, and depths of 10 and 20 feet, 30


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here the depth is the surface width, and the slopes contain the same quantity of earth which the bed itself contains.

Now take two other cases in which the widths shall be the same as in the former case, but the depths different, say widths, 15 and 30, and depths of 5 and 30, in this the depth in the first example, is less than is required for equal expense, and in the second it is more, and the ratios are 37.5: 75 and 1350: 900; that is, in the first case the bed costs twice as much as the slopes, and in the second it is only the cost of the slopes, hence for heavy work, similar in character to that upon the first division, the ratio is in favor of the double track.

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