obstacles they may encounter. I am afraid that it will take them from three to five days to reach Richmond. When these barges have once passed, it will enable all necessary supplies to be forwarded to New Carthage, unless prevented by a fall of the river. The river has been falling one-half inch per day for the last two days. The steamboat and barges cannot be passed through the proposed passage, as shown on sketch sent with previous letter, but will pass through field beyond small bayou (James'), and enter Walnut Bayou by wide ditch at Culberson's plantation, as indicated by the other line of sounding. This route will be used until the other is prepared, which I deem indispensably required to keep the stage of water in Walnut Bayou as high as possible in case of a fall in the river.

Captain Kossak has completed the four casemate batteries between railroad and angle of levee north of it. The two 30-pounder (Parrott) guns opened yesterday morning, but with no very decided results.

The fire is to be continued to-day. Captain Kossak has been directed to hand in a report with respect to these batteries, which will bee forwarded to the Department as soon as received.

I am, general, very respectfully, your obedient servant,

FREDERICK E. PRIME,

Captain of Engineers.

Brigadier General JOSEPH G. TOTTEN,

Chief Engineer of the Army.

HEADQUARTERS DEPARTMENT, OF THE TENNESSEE,
Milliken's Bend, La., May 4, 1863.

GENERAL: Since my last report, of the 18th ultimo, the water has fallen to such an extent as to prevent most of the work on the canal from being prosecuted. The two dredges at the entrance of the canal have been drawn out and brought to this point. The other two cannot be removed, one being hard aground and the other having barely enough to work into the bayou. Twenty-odd barges are in the bayou at and below Cooper's plantation, which there is but little prospect of moving to Richmond until a rise in the river. Major Tweeddale, with some four companies of his regiment and the One hundred and twenty-seventh Illinois Regiment, is engaged in damming the Roundaway Bayou, below Richmond, so as to prevent the escape of water to the westward as much as possible. The change in the river level is shown by annexed statement,* obtained from Colonel Wilson's topographical office. There are two barges in the Roundaway, and Major Tweeddale thinks that, if his dam succeeds, they can be used advantageously in moving supplies from about 2 miles above Richmond to New Carthage.

On the 2nd, Captain Freeman, with Lieutenant Lochbihler's company, moved to the front with the pontoon train (India-rubber)-20 pontoon wagons, 2 abutment wagons, and 1 supply wagon. No trestle pontoon of the bridge sent, as it was not ready.

The guns were withdrawn several days since from the casemates below the canal, and I am informed their casemates were burned by the enemy some two nights since. I have neglected to mention that the Victor, the small steamboat referred to in my last report, did pass through the canal and the bayou, and is now in use below New Carthage.

Colonel Pride left several days since for the North. All of the pioneer

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*Omitted.

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