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that is inadmissible on account of the coal.interest. The following quantities of material were used : 2,815 cubic yards of stone, 5, 109 cords of brush, and 705 piles. The total length of the new dike is 2,000 feet.
Henderson Island Dike, seven hundred and ninety-seven miles below Pittsburgh. At the close of 1873 this dike had been extended into the river 1,000 feet. Its effect was excellent from the first, a good channel haring been maintained throughout the low-water season, Unfortunately this good effect was not lasting. During low-water of June, 1874, the slight obstruction to the flow of the river occasioned by the dike was enough to cause the channel behind the island to cut out, and in extreme low-water steamboats had to take that route. This channel was very narrow and intricate, and was full of snags and water-soaked logs, making an exceedingly bad place for steamboats, and one quite impracticable by night. I made a careful personal examination, tinding 31 feet at the head of the chute, and less than 3 feet in the old channel, the river being a foot or two above dead low. No steamboat could get through the chute without hitting at least one log. I concluded that the proper remedy was to close the chute entirely by a pile and brush dam, thus forcing all the water through the channel marked out for it. This work was approved by you, and is now under way. At present the dike is finished for a distance from shore of 1,050 feet, and piles have been drived for an additional distance of 250 feet. It will be extended to a total length of 1,500 feet.
I have always been apprehensive of the possible need of a dam behind Herderson Island, but I was unwilling to spend the money needed to build it until its necessity was demonstrated, and the fact that in former years no such dam bad been built strengthened me in my conclusion that it might prove unnecessary now.
Nere drenge and dump-scous. The new dredge Oswego and two dump-scows bave been built by Mr. S. B. Alger, under his contract of July 11, 1873. The hull of the dredge is 75 feet long and 30 feet wide, with 5 feet 9 inches depth of hold. She draws 2 feet 8 inches of water when loaded with 600 bushels of coal. Her cylinders are 10 inches in diameter, with 14 inch stroke, and she is provided with one of King's marine-boilers, baving eighty 3-inch return-flues. A steam boisting-apparatus is provided for the forward spuds, and a steam-capstan for maneuvering. The clutch used is Alger's patent friction.clutch. It is somewhat liable to breakage, but when in order works rapidly and well. By making it of steel, and keeping a spare clutch on band, there need be no serious loss in case of accident. The scows are side-dumpers, with bi!is capable of holding 71 cubic yards. They are 65 feet in length and 20 feet in width, and have 4 feet depth of hold. They are built without crown or sheer, and draw when empty 15 inches. They can carry 50 cubic yards of gravel on 3 feet 6 inches of water. The contract-price of dredge and scows was $18,500. An additional sum of $2,000 was spent on outfit, making the total cost of dredge and two scows about $20,500.
Iron hull snag-boat.-The contract for building the hull of the iron spag-boat for the Ohio was taken by the Swift Iron and Steel Works, at $84,350. During the winter but little work was done, on account of the financial depression and of strikes at the works. At present everything is progressing rapidly, and the hull is about one-third finished. Its construction will supply a long-felt need.
Trareling sands in the Ohio below the falls.-The greatest obstacle to the successful improvement of the Lower Ohio comes from the enorious masses of sand and gravel that travel down stream during erery rise.
Behind the dikes at French and Henderson islanıls, and at Evansville, sand-bars have forined as high as the dikes, and in place where before, or during their construction, there was deep water. At the Cumberland Island end of the Cumberland dam, where last season there was about 10 feet of water, there was this season 10 feet of sand, showing a deposit of 20 feet in one season. The sand behind the dikes mentioned above is mixed with gravel, and as it is impossible for gravel to be carried in suspension, it must have rolled along the bottom The up-stream sides of the dikes are vertical, or nearly so, and I can see but two ways for the gravel to get over the dike. It might have reached the upper live of the dike and there got attached to ice which carried it over when the river rose, and then dropped it below the dike. This action has undoubtedly taken place at Louisville, at the revetted slope on the upstream side of the dain at the head of the falls. The other supposition is that in high water the bottom of the river was raised by deposit to the level of the dike, and that before the dike became visible the deposit on its up-stream side was washed away. This I think the more probable explanation, especially in view of the fact that during the ice-period of last winter ail of the dikes were submerged many feet. There is abundant additional experience to show that during high-water the bottoin of the river is habitually raised by deposit, and that the low. water channel is subsequently cut out of it as the river falls. This con. dition makes the radical improvement of this part of the Ohio a matter of serious difficulty. A further discussion is reserved for the report on the radical improvement of the Ohio, which has been ordered for the Senate Conmittee on Transportation.
The work of dredging has been vigorously prosecuted during the year, under the direction of Mr. E. J. Carpenter, assistant engineer. Onthe 1st of July, 1873, the “Ohio" was at Captina. The cut at this place was finished by the removal of 260 more yards, and the dredge was moved to Butlington Island. The “Ohio” continued work on the bar at this place, which is one of the worst on the river, until compelled by cold weather to lie up. She dredged 8,983 cubic yards in July, 10,285 in August, 11,907 in September, 6,662 in October, and 2,760 in November, making a total of 10,596 cubic yards. During the last month the new drerige Oswego joined her, but neither dredge could do much, on account of high-water. The work of the “Oswego” amounted to but little, as all of her machinery was new and required to be worked into smooth running. The little dredging done by her bas been credited to the “ Obio.”
The dredges were laid up at Marietta in the mouth of the Muskingum until the 1st of May. They were then sent to Pittsburgh to remove the bar at the foot of Brunot's Island, which gave great trouble to coalfleets. Sixteen thousand two hundred cubic yards were removed in May and 21,839 in June, making a total of 35,038 cubic yards removed from the bar. So further difficulty is anticipated at this place. The dredges are still at work, but their subsequent operations belong to the present fiscal year.
REMOVING WRECKS AND OBSTRUCTIONS.
The winter of 1872–73 was unusually severe, and when the ice broke up it destroyed many river-craft, and left numberless wrecks in the channel which could not be discovered until low-water of summer,
Capt. R. W. Dugan, with the boat of the same name, blew up and re. moved the wreck of a section of dry-dock that bad lodged in the channel at Rising Sun, and the wreck of the steamboat McCullongh near Madison, Captain Hobson, with a crane-boat, remored several logs and minor wrecks in the immediate vicinity of Cincinnati. There were several wrecked coal-barges in the channel at Vevay. I tried to get a dredge from the Louisville Canal for this work, but, being unsuccessful, I made application to the Kanawba board, and was permitted to hire a dredge from them. This dredge removed the barges at Vevay, but a sudden rise in the river compelled her to stop work and return to the Kanawha. In August one large log was removed by a crane-boat from the channel at Cullum's Ripple, and another lying opposite Covington.
The navigation of the Ohio being greatly hindered in low-water at Mustapha Island, Guyandotte Shallows, Poag's, Jenalt's, and other places, I had a large grapple built for the express purpose of removing bowlders. This grapple is 11 feet in height, has a grasp of a little more than 5 feet, has four fingers on each side, weighs 2,700 pounds, and cost $1,174. The following obstructions were removed by the use of this grapple: the rocks at the foot of Mustapha Island, where the channel is now in good condition; several rocks in the channel-span of the Parkersburg bridge, carelessly thrown there by the bridge-builders, and two snags between Parkersburg and Marietta. This grapple bas been used to great advantage on the Great Kanawha. For details, ref. erence is made to the annual report of operations on that river.
A snag was removed by hired labor from the foot of Ranty's Shallows, and the Government snag-boat S. H. Long was borrowed from Major Suter, engineers, and was employed four days in cleaving out the chute at the head of Cumberland Island.
During October, four troublesome snags were removed from Quick's Run Bar by a hired crane-boat. A section of the dry-cock was blown up at the foot of Ludlow street, Cincinnati, and the greater portion of the wreck of a stone-boat was removed from Rising Sun bar. A sudden rise in the river prevented its entire removal.
A wrecking party provided with diver, armor, battery, and torpedces was equipped and put to work at the wreck of the Missouri, a very large and strongly-built steamboat, lying just above the Evansville dike. About balf of this boat was removed by the close of the season.
Iu May, one log was removed from the mouth of the Muskingum, and three others from the head of Blennerhassett's Island.
The oflice-work during the year has comprised the preparation of a continnous map of the river, on the scale of 2 inches to the mile, of detailed drawings for the snag-boat, of hydrographs of the Ohio River gauge-records, of drawings to accompany the report of the Board of Engineers on movable dams and hydraulic gates, of drawings and tracings of special surveys, and of miscellaneous work of various kinds.
ESTIMATE FOR 1875–76.
The first question to be settled is the general method of improvement. After long study, I have come to the conclusion that the best method of improving the Ohio, at least in the upper part of its course, is to follow the plans that bave been so successtul on the Seine, Yonne, Marne,