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Fort Calhoun to De Soto, a distance of five miles, it is level, passing through about three miles of timber directly at the foot of the bluff, and two miles of prairie.

De Sota to Cumming City, seven miles, one of which is upon high, rolling prairie, and six upon bench land. Cumming City, via Tehamah, to Decatur, about thirty-two miles, the route is level, upon bench lands. We here pass into the Reserve, eighteen miles in width, the entire distance of which is high, rolling prairie, known as the Blackbird hills, skirting upon the timber in the gorges putting into the Missouri. By winding with the ravines and ridges a very fair road can be obtained.

This brings us to the foot of the bluffs, where we have the bench lands of the Missouri to Dacota City, a distance of nine miles.

We start immediately upon the reconnaissance from this place to the Running Water, and, owing to the mail facilities, will not be able to forward a report of this portion of the route until after our return to Dacota City

All of which is most respectfully submitted.
I have the honor to be, very respectfully, your obedient servant,

GEORGE L. SITES,
Superintendent Wagon Road from Platte to Running Water.

APPENDIX A. Statement of the number and character of the bridges which will be re

quired, and the facilities for the construction of the same, between the

Platte river and Dacota City. Papillion creek, bridge 60 ft., timber within 1 mile, steam saw-mill 14 mile, cost. $900 Creek S. of Omaha, 30

1

1

400 Ravine N. of Omaha, 15

2

1

100 Spring creek,

50
3

3

800 Ponca,

30
1

1

400 - creek S. of Calhoun, 15

11

11

100 - creek S of Calhoun," 15

21

24

100 Voore's creek,

70
1.

950 Mill creek,

25
2

3

250 Glover's creek,

12
1

11

75 South creek,

12
4

6

75 North creek,

20
4

7

150 New York,

9

12

900 Pike creek,

30
11

14

400 - creek,

20
12

9

150 creek,

20
12

8

150 - creek,

10
12

7 Tekamah creek,

50
4

800 Silver creek,

50
}

800 Elm creek,

40
1

600 Wood creek,

40
1

1

600 South Blackbird,

75
2

8

1,000 North Blackbird, 75

1,000 Omaha creek, 70

5

950

60

75

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Grading

11, 725 3, 275

15,000

Bridges are not absolutely necessary across Moore's creek and the two Blackbird creeks, as fords can be obtained by cutting down the banks, which, however, are very high and steep; but these streams will often be impassable on account of high water, and, if possible, bridges should be built across them for the convenience of the travelling public.

The cheapest and simplest plan for all the bridges on this road, I think, is as follows:

The abutments to be formed by driving piles to a solid foundation, in a row, and sawing them off to a proper level, and connecting them at the top by a cap-sill; and they may be further secured by diagonal braces halved to the uprights or pinned to them. For the longer bridges there should be several bents placed parallel to each other, and firmly connected together by cross pieces. Where piles cannot be driven, a grillage may be formed by laying square timbers horizontally across each other and securing the uprights to them, and the grillage retained by an enrockment; or the abutments may be made of cribs composed of large square timbers, halved into each other and otherwise firmly connected with iron bolts or wooden braces, the enclosed area being filled with stone or earth.

THE FRAMES.

For a bridge not exceeding 12 feet sleepers are to be laid parallel to the direction of the road-way, resting on the supports, to which they are notched or pipped with iron bolts, and the flooring nailed down on them.

If the bridge is from 12 to 20 feet long short pieces, termed corbels, will be placed on the caps of the piers or abutments, which will serve the purpose of lessening the bearings. When the bridge is over 20 feet long the corbels will be supported by struts. When the bridge exceeds 30 feet and is less than 40 feet in length, it will be best to displace the corbels and put a straining beam in the middle of the sleepers, and sustain it by two struts. For bridges above 40 feet in length it will be necessary to use both the corbels and straining beam.

In the above cases the floor rests on the frame. In some of the bridges to be constructed it will be better for the flooring to be suspended from the framing. For this purpose the simplest arrangement will be to have a tie-beam resting on two supports, with two inclined pieces mortised near the ends of the tie-beam, and abutting against an upright or king post placed in the middle of the tie-beam. The cross joists are laid on the tie-beam, and with it are suspended from the inclined pieces by means of the king post.

For bridges between 40 and 100 feet long a straining beam should be placed between the upper ends of the inclined pieces, and suspending the road-way and tie-beam from these points by two stirrup pieces termed queen posts; and diagonal braces should be placed in the space between the queen posts and tie-beams.

The points where joists may occur in the sleepers or chords should be supported by iron castings, and the stirrup pieces or uprights should be well strengthened with large iron rods. In locating the road it may and probably will be necessary to make some change in the plan of a few of the bridges. of Dacota City, it is 31 miles, in a due west course, through the bottom to the south bank of the river as it comes from the west, and just before the river has taken its great bend; whilst the distance between these points by the river is estimated at 20 miles.

HENRY B. SMYTH,

Engineer.

BELLEVUE, NEBRASKA TERRITORY,

August 10, 1857. SIR: I have the honor to herewith enclose my report for that portion of the route for a wagon road between Dacota City and the Running Water.

I would also acknowledge the receipt of a letter dated the 9th of July, 1857, from Albert H. Campbell, general superintendent Pacific wagon roads, advising me that $3,000 of the appropriation would be reserved to meet unforeseen contingencies, &c.; also a communication from the department, modifying my instructions, dated the 11th of July.

The latter part of the 4th clause of my instructions of the 15th of May indicates that “further instructions for my future government will be given upon receipt of my reports. I have not as yet received any further instructions subsequent to the receipt of my report of the 10th ultimo. I have the honor to be, very respectfully, your obedient servant,

GEORGE L SITES,

Superintendent Nebraska Wagon Road. Hon. JACOB THOMPSON,

Secretary of the Interior.

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We left Dacota City on the 11th of July and travelled over the bottom N. 75o W., S. miles, where we struck the bluffs, which are low and regular, and of easy ascent; in nearly the same direction we passed over the divide about one mile, when we came into the Elk creek valley ; passing up this valley for about three miles in about the .same course we ascended by an easy grade upon high prairie, somewhat rolling, but eligible for a road without grading, over which we passed to Ayoway creek, at a distance of 7,163 miles; thence up Ayoway creek valley N. 69° W., 11%, miles; thence north seven miles over rolling prairie, somewhat rough, on to Lime creek. This direction was taken so as to avoid what is known as the Lime creek hills, which cover an area of about eight miles square. They are cone-like in form, with but little vegetation, very precipitous and rough from washings by the rain. The ravines are short and abrupt, forming deep gulches. Through these hills there is a circuitous divide, or carrow ridge, very hilly, with a rough surface, caused by washing, over which a road, in my opinion, is impracticable, on account of the increased length of the road, the narrowness of the top of the ridge, the abrupt ascents and descents, and the unevenness and roughness of the surface. From Lime creek we passed, in a westerly course, over a divide, into the Missouri bottom, subject to overflow, which we soon left for the bluffs. Passing over these bluffs, at a distance of about ten miles from Lime creek, we came upon a high prairie, slightly rolling, looking down upon Bow creek valley to the westward about two miles ; here we changed our course to N. 35o W., and at the distance of three miles we came into the Bow valley, which, at this place, maintains a width of about one mile ; thence along the valley in the same course about four miles to the crossing of Bow creek. Here we crossed upon a temporary bridge, from which we bore N. 45° W. up the valley of a very sluggish stream (a tributary of the Bow) for about four miles; thence S. 70° W. on a level prairie to a small creek, believed to be the west branch of the Bow, which we crossed by fording at a distance of nine miles from the main Bow. In looking immediately to the west we saw nothing but sharp cone-like hills, which induced us to take a course S. 45° W., along and over a divide three miles to a small stream, with water clear and cold, to which we gave the name of Campbell's run. Here we found a spring running from a chalk bank; the water was excellent and very cold. We again started due west, crossing the run at a ford with a stone and gravel bottom, and passing up a wide ravine bearing to S. of W., and down another we came, at the distance of 31 miles, upon the valley of a creek called by us Smyth's creek; the banks of this creek were high and perpendicular, Passing up the valley nearly south for about three miles, we here anhooked our horses from the wagons, and, after crossing the horses, we attached ropes to our wagons, and with the horses pulled them over. We again started on a westerly course and soon reached a high divide, the general direction of which appeared to be about NE. and SW. To the westward, as far as the eye could reach, we saw nothing but a succession of hills and ravines, with a range at the horizon, supposed to be about twenty miles distant, much higher and more abrupt in appearance than those in our immediate vicinity. On looking to the N. and NW., at a distance of from five to eight miles, we could distinctly trace the meanderings of the Missouri river. We here became confirmed in the opinion entertained after leaving the Bow valley that an eligible route for a road could not be obtained in the direction of the l'Eau qui Court from Ayoway Creek, unless we should be able to find streams, the general direction of which should be to the north of west; unless, indeed, we should pass much further to the south than the point to which we were to run would justify. We were satisfied that such streams were not likely to be found so near the Missouri. We therefore kept upon the divide, running in a southwesterly direction, surveying minutely the character of the country at every point of the compass. Immediately to the SW., we saw (what we afterwards found to be very noted) a lone tree about five miles distant, standing at the head of a ravine, perhaps fifty feet higher than the divide upon which we then were, and a few yards to the south of this tree the divide appeared to reach its greatest altitude. From this point we could view the whole surrounding country; to the N.NW. and W. we could see nothing but interminable hills and ravines, whilst in the distance we still observed this range of hills bearing apparently SE. and NW.; to the south, whilst the general appearance of the country was rough and broken, the hills gave evidence of more regularity, and to the SE., at some distance, we discovered and particularly noted a valley of considerable extent bearing E. and W., the waters evidently flowing to the east. Upon reading the odometer we found we had travelled eleven miles from the crossing at Smyth's creek. Still continuing on the divide, we saw to the south of west a grove of timber, which we reached about sunset, having travelled four miles since the last reading of our odometer. Here we found a beautiful grove, which we afterwards learned was called “Secret Grove,” entirely surrounded by high hills, except the opening toward the north made by the ravine in which the grove is situated. The bed of the stream was dry at this time, but we found a deep gulch filled with water, sufficient for ourselves and horses. We crossed the ravine upon a temporary bridge constructed by our party, and bearing to the west we ascended a high ridge, from which we again saw to the N.NW. and W. the same high range of hills observed before; and in looking down irregular ravines at several points as we passed to the SW., we discovered timber marking the course of a stream which we had good reason to believe would be found difficult to cross. We therefore continued our course to the southwest, toward a high bluff bank in the distance, crossing a small run (which we afterwards ascertained to be the east branch of Bazil creek) and valley at a distance of eight miles from the grove. Whilst it was observed that this valley led in the direction of our proper route, it also led us down upon the creek that we were avoiding or trying to head, which we supposed could be done at or near the bluff banks. Continuing in the same course, we passed across a valley without water and up a ravine to the south of the bluff

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