ration on about twenty miles of the canal. The soil of The soil of a considerable portion of this distance is a strong clay, in which very little water can be lost by soakage; and even the most unfavorable parts contain so considerable a mixture of clay, that, with a very little care in the construction, they may be rendered nearly water tight. Under these particular circumstances, I consider 22 cubic feet per mile per minute, as entirely sufficient for the supply of these losses on the middle division; which gives a total of 440 feet for the 20 miles. One hundred and twenty cubic feet per minute, must then be allowed for leakage and waste at the gates; which, with the former, being deducted from the total supply, leaves 326 cubic feet per minute, for the purposes of lockage, or 234,720 cubic feet per diem, at each end of the summit level. The locks are of six feet lift, 15 by 90, and contain 8,100 cubic feet; this quantity, therefore, will afford nearly 29 locks full, and as these locks full will generally pass four boats, in the average order in which they present themselves, we have a navigation of 384 boats per diem from the supply in question. This seems a very moderate number; but let us examine it a little further; and first with reference to the question of revenue. Thirty-eight and a half boats per diem, during the Summer months, correspond, according to the ratios furnished us by the New York canal, with an aggregate of 10,000 boats per annum; and if we suppose an average cargo of 25 tons (the burden of the boat being full 50) we shall have a total of 250,000 tons, and a toll, at one cent per mile per ton, of $226,250 per annum, or nearly 18 per cent. on the whole cost of the canal. Let us also examine it with reference to public accommodation. At Rochester, on the New York canal, the average number of passengers per diem, during the months of August and September, 1828, was about 27, and from circumstances communicated in the last report of the commissioners, I infer that it must have been even less than 24 during the past season; the probable mean is about one half less than the number which could have been passed during the same months, on the Sandy and Beaver canal, with only the natural supply of water on the summit; and if we admit the trade of Rochester to be a fair term of comparison, it does not appear probable that the business of the Sandy and Beaver will immediately require a larger supply than this. That it may do so, however, in the course of a few years, is by no means unlikely. Its object is to connect the trade of the Ohio canals, by a direct route with Pittsburgh and Philadelphia, and ultimately, perhaps, with Baltimore and Washington; and if we may infer an increase of trade, corresponding in any degree with the advancement of population and public wealth in the State of Ohio, the time is not distant when other supplies will be called for. In this case, we look to the middle fork as already suggested, and I now proceed to show the manner and probable expense of obtaining any required addition of feed water from this stream. The point at which it is proposed to take it out, is 68 chains from the line of the summit location, opposite the end of the second mile, and 125 feet below the ground rising immediately from the edge of the creek to the level of the line. A few yards from the water, and near the level at which the steam engine would be placed, a rich vein of bituminous coal breaks out, and shows itself with a thickness of about three feet, to a considerable distance up and down on both sides of the creek. This coal has been wrought to some extent at the furnace a short distance below, and it is fully ascertained that it may be delivered at the mouth of the pit at one and a half cents per bushel. I have estimated it at 2 cents, delivered at the engine, which makes the cost of fuel only 4 dollars for an engine, consuming two hundred bushels per diem. The total cost of a feeder, deriving its supply by an engine of this power, kept in perfect repair, and working at the rate of ten weeks per annum, may be estimated as follows: For the engine, and the necessary buildings, 200 yds. main pipe, at 24 dollars, 1,200 yds. wooden leader, 4 dolls. Total first cost, $10,000 00 6,000 00 5,000 00 $21,000 00 Fuel as above, at 4 dollars per diem, 10 weeks, $280 00 350 00 $630 00 $10,000 00 Total annual expense, Say 700 per annum, equivalent to an investment of Total capital, $31,000 00 The performance of the engine will depend upon its construction. This is differently estimated by different engineers. According to the performance of the Cornwall engines in 1815, an engine consuming 200 bushels of (English) coal per diem, would raise about 400 cubic feet per minute, to the height required; but from the work of the engines of the same district, in 1828, such an engine would raise no less than 670 cubic feet. Taking the mean of these results, and making a reasonable allowance for any supposed difference in the quality of the coal, I get 460 cubic feet per minute, by way of estimate, for the performance of the engine in question, which is also a fair estimate from the working powers of several engines in our own country. This will increase the quantity of lockage water from 326 to 786 feet per minute, and the capacity of the canal from 384 boats per diem, to 93 boats. A trade to this extent, during the Summer months, according to the ratios heretofore quoted, corresponds to a navigation of 24,111 boats per annum, (almost double the number of arrivals and departures at Albany during the past season) and an aggregate toll of 542,400 dollars. These calculations are made upon practical grounds, and with liberal allowances on all points which involve any doubt. It may be satisfactory to some, however, to know, that, in case of necessity, the middle fork could easily spare 3 or 400 feet more, without prejudice to the supply of the Eastern division. The summit level being thus provided for, there can be no doubt of the sufficiency of water on every other part of the canal. On the Western division, some additional supplies will be gained at the dam below Lock No. 7, which, with the small streams intersected by the line below, will be more than sufficient for the soakage and evaporation to Pekin. Below Pekin, and after taking in Hagill's Run, there will be surplus sufficient to admit an increase of two or three feet in the lift of the locks; and finally, from Waynesborough down, the locks may safely be constructed, if necessary, with lifts On the Eastern division, there will be a sufficiency for 10 feet locks, immediately after taking in the first feeder from the middle fork of ten feet. above New Lisbon; and from that point down, locks of 9 and 10 feet may be used without fear, so far as water is concerned. It only remains now to add a few remarks on the construction of the works, and the scale of prices, preparatory to the estimate. ter. The connexion of this canal with the canals of Ohio and Pennsylvania, (both modelled after the New York canal) indicates, at once, the tonnage of the boats to which it should be adapted, and the size and proportion of all the works. Accordingly, the section of the canal has been assumed at 40 feet surface, 28 feet bottom, and 4 feet deep, and the locks at 90 feet by 15. The profile of the summit level only, is varied as already suggested, so as to admit a depth of seven feet instead of four. The tunnel is projected with a transverse section of 30 square yards, except two recesses of the length of 75 feet each, which are enlarged to 50 square yards, making an average of 334 on the whole length of the drift. This goes upon the supposition, that the tow path is discontinued through the opening. It could not be retained without an additional expense of 15 or 16 dollars per yard run; and its use may easily be supplied by an endless chain, and stationary horse power, for less than one-tenth that amount. The feeder from Davis's Branch, it is proposed to construct of wood. It will not differ much in point of expense, from an excavated feeder, and will have greatly the advantage in retaining the waThe dams, generally, are supposed to be built in the usual way, of timber, filled in with stones and gravel; the aqueducts with trunks of wood; and abutments and piers of masonry. Good materials for masonry are found every where, within a short distance of the line, and in many places, where the most expensive constructions are required, the best of building stone occurs on the spot. With these advantages, the locks and other works of masonry would probably be executed at less expense (perch for perch) on this line, than on canals generally; but as many of the locks are of moderate lift, and on that account somewhat more expensive in the gross, I have estimated them at 600 dollars per foot throughout, which is a very liberal average of the lock contracts on the Pennsylvania canals. Other works are estimated by a scale equally safe: as for instance, excavation of earth, generally from 7 to 10 cents, and in deep cutting, as high as 16; rock, in ordinary situations, 35 to 50 cents; in the shafts of the tunnel, $125, and in the drift of the tunnel 2 dollars; embankments, 10 to 15 cents; dams across small streams, and of moderate elevation, 4 to 9 dollars per foot; those of greater height, 15 to 25 dollars; aqueducts, 35 to 50 dollars per foot run; tow path bridges, farm and road bridges, and culverts, according to the prices on the western division of the Pennsylvania canal. The aggregate result per mile, is exhibited in the following summary estimate, together with the causes of extra expense, whenever they occur: 2,800 00 20. Dam and guard lock 21. Fair 22. Dam, and guard lock, and feeder from North Branch 11,903 44 23. Fair 24. Dam and guard lock, extra rock, &c. 25. Undulating 26. Dam 27. Fair 28. Slack water 2,676 40 15,679 56 4,620 36 30. Aqueduct 31. Undulating Do 29. Dam and guard lock, extra embankment and aqueduct 33,167 36 6,927 56 4,012 24 32. 4,512 26 3,024 17 5,803 70 3,458 00 5,114 40 37. Extra cutting 4,347 76 38. Fair 2,870 39 39. Extra cutting 4,940 76 40. Protection wall 4,836 28 41. Embankment and aqueduct 7,370 41 42. Slope wall 9,304 40 43. Fair 3,196 52 277,802 77 429 feet lockage at $600 257,400 00 Total, $535,202 77 |