STEAMER MAGNOLIA,

Opposite Vicksburg, February 16, 1863.

GENERAL: I have the honor to acknowledge receipt of Department letter of February 5, with respect to funds applied for. The water in the river has been very nearly at the same level since my last letter. Work on the new entrance is progressing; this work is done by contrabands. Between the levees but little work has been done as yet by the troops, on account of the bad weather for the past two days. The water in the canal has been drawn off by a cut leading into the low ground to the westward; it is now about 7 feet below the level of the water in the river.

Colonel Bissell's engineer regiment, which arrived yesterday, will bee employed extracting the stumps in the present canal, and also in the proposed enlargement, and in clearing a channel of 200 feet in width through the lowest part of the swamps and low ground between the canal and crevasse at Johnson's plantation. The water-marks on the trees are 10 feet above the soil, and even now it is probable a depth of from 5 to 6 feet could be obtained by allowing the river to flow into these bottoms. This new channel would be tried in case too heavy a fire should be brought to bear by the rebel batteries on the present outlet of the canal. A few shells and shot have been thrown about 100 yards north of the lower levee from batteries above and below the outlet of the canal; there is, therefore, a cross-fire, though as yet there is nothing to indicate the existence of an enfilading battery.

Mr. Halleck, engineer clerk, who leaves to-day for Memphis, will, on his arrival, forward by Adam Express to the Department the original map of Corinth, our approaches, and the enemy's works. He will also transmit at the same time all weekly reports connected with the works at Corinth and Memphis. To complete the record with respect to the works at Corinth, I have directed Captain Kossak to draw up a memoir thereon, extending up to his first weekly report.

I have experienced much difficulty in making the necessary surveys at Memphis and Corinth, for want of proper instruments. I have, therefore, to request that a surveyor's compass and tripod, a level and tripod, and three pocket compasses may be sent to me by the engineer agent at New York, through Adams Express. I shall on receipt of the level be able to furnish the references of interior crests of works at Corinth and prominent points in the neighborhood, which will render the drawing complete.

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

FREDERICK E. PRIME,

Captain of Engineers.

Brigadier General JOSEPH G. TOTTEN,

Chief Engineer of the Army.

STEAMER MAGNOLIA,

Opposite Vicksburg, February 21, 1863.

GENERAL: I have tho honor to report that we have had but two days favorable for work since my letter of the 16th (the 19th and 20th). To-day it is again raining. The troops are at work on the part of the canal assigned to them. The steam pump was started on the

19th, and answers well in keeping the new entrance of the canal clear of water. It is only worked to one-half of its capacity, and even then is sucking most of the time. Colonel Bissell's engineer regiment, with the ex