other circumstances we could, without a doubt, capture Mobile, recapture galveston, break up that most damaging contraband trade across the Rio Grande, penetrate the Red River country, by means of the Teche and the Atchafalaya Bayous; but for any one of these vitally important movements we are wholly unprepared, on account of the deficiency of suitable naval and transport vessels. We are especially in need of vessels of light draught of both classes. The Government cannot strengthen its cause better than by increasing its fleet here - an increase of force which must be obtained before any great success can be obtained here, and is imperatively demanded to maintain our position.

The enemy is concentrating its naval and land forces in this quarter. There is the most imperative necessity for this on the part of the Confederate Government. I am sure, perfectly sure, that I don't under-estimate, from personal considerations,the importance of other enterprises or over-appreciate the duty with which I am intrusted when I say that the rebellion is ended with the opening of the Mississippi River. I desire the Government to consider the suggestion, which I make in the most solemn conviction, that its control in either hands is decisive of the great conflict. On the upper rive we are strong, and, with time,we shall succeed. It requires time, and, with adequate means here, our success is certain; it is beyond a doubt, but it requires time here also, and an increase of our forces. We are isolated, cut off from assistance or retreat, assailable on all sides, and should be strongly supported, as the possession we hold is vital.

The opening of the trade would, in a few weeks, give me all the transports I require, because trade is drawing the proper class of vessels here with great rapidity. In a month or two we shall have abundance. I am amazed that the Government should have had possession of his position for nearly a year and find only twelve or thirteen vessels, in private and public service, adapted to its navigation,and these, in great part, decayed and unsafe.

Information was received on Wednesday, the 4th instant, that several regiments of Virginia and Georgia troops had recently arrived at Camp Moore, on the Jackson road. This is a position from which they move with equal facility upon Port Husdon, Baton Rouge, or New Orleans, via Pass Manchac. The increase of pickets of the enemy on the east side of the lake (Pontchartrain) and on the railroad has indicated some movement in that direction, and the capture of two schooners about 2 miles below Pass Manchac (a report of which is forwarded herewith) strengthens such views. The report is common among the sympathizers with the rebels that the city will be recaptured, and the same rumors are circulated in some of the parishes in the direction of La Fourche. We are, however, as well prepared for them as possible. Many guns have been unspiked and set up since my arrival he, and fortifications are in progress at important points. We have a close observation upon all the avenues in the direction of Camp Moore and Jackson, of the Red River, and also upon the Mississippi.

I have cut off trade with the enemy entirely, by authority. Whatever is done in furnishing them supplies is done against orders. I have authorized the parties who make captures, or who give information leading to captures, to claim and receive one-half the value of the supplies so captured.

I have declined to allow any supplies to be sent across the line as an equivalent for cotton, &c. Cotton that comes in for sale here is not confiscate or disturbed.