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ent was then engaged. Since that period, the only alteration in the channel at this work, consists in the removal of some of the bars, and the formation of others, giving evidence of a gradual movement of the sand and gravel, by the current of water which the dam forces into the channel, and leaving little doubt of the final result. It is the intention of the superintendent to raise this dam still higher, by which the accomplishment of the desired object will be more speedily effected. The accumulation of sand and gravel above and below the dam, while it gives assurance of stability to that work, likewise affords satisfactory proof that the channel on the east side of Cumberland island is rapidly enlarging its dimensions. When we take into consideration the immense mass of sand and gravel that a year ago obstructed the eastern channel, sufficient, in quantity, to form a bar across the whole width, three feet above low water mark, and running a considerable distance up and down the stream; and when it is remembered that this mass, which moves slowly and with difficulty, has to be swept, by the force of the current, into the deep holes about the mouth of the Cumberland, a quarter of a mile below the bar, it is not surprising that, in its progress towards these holes, it should collect occasionally in lumps, causing uncertainty and difficulties in the navigation inseparable from the means used for the improvement of this part of the river: the ultimate success of this work is no longer doubtful.

It is probable that the current would already have opened this channel entirely, but that it only operates during that portion of the year when the water is below the level of the top of the dam, and is consequently forced into this channel. Little alteration is perceptible at the Sister islands since my last report. The channel on the east side of the island has so far filled up, that at the present stage of the river (seven feet above extreme low water) scarcely any of the stream passes on that side. The sand bars have extended themselves at the foot of the island, confining the volume of water to a narrower space; the extremity of the bar which projected from the east shore opposite Bay creek, has been partially washed off; boats are not now compelled to approach so near the west shore as formerly. There is a small break in the principal dam at this place, near its head, noticed in a former report, and also on a sketch forwarded to the Department, which has been considerably enlarged since the last inspection, and will ultimately injure this work if not arrested in time. The Sister islands were once among the worst places on the river; at present they offer no obstruction to the navigation. This remark will apply, in a great degree, to Scuffletown and French Island bars. Three Mile Island dam is not yet finished, but will be commenced early in August. It is the intention of the superintendent to employ the forces designed for removing the raft on Red river, upon the Ohio, until the season for recommencing the former work. By this judicious arrangement, these works serve as a rendezvous for collecting laborers during August, September, October, and a portion of November, which are the only months when the services of men could be profitably employed on the Ohio, leaving time, after the suspension of these works, to transport the forces as early as it is expedient to commence operations on Red river. Notwithstanding the space over which the works entrusted to the superintendence of Captain Shreve are spread, by his judicious and systematic division of the time, each appears to have received all the attention that it required. I have the honor to be,

Very respectfully, your obedient servant,
A. H. BOWMAN, Lt. of Engineers.

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