repairs, which will require the expenditure of about $500. they are-1st, replacing three water cask and the old banquette on the gorge; 2nd, repairing one of the cisterns and the old palisading, which, though much rotten, may at a trifling expense be made to answer for the present; 3rd, making six shutters for the embrasures and doing some slight work to the main gates. Two mortars and a few other articles belonging to this work were taken to the United States Arsenal in Charleston some months since for repair. They are still there. I shall ask the officer in charge to return them s soon as he can. The magazine is not a very good one; it contains some rifle and musket powder, said to be good, and also some cannon powder reported damaged. The powder belongs to the arsenal. It is, in my opinion, essentially important that this castle should be immediately occupied by a garrison, say, of two officers and thirty men. The safety of our little garrison would be rendered more certain, and our fort would be more secure from an attack by such a holding of Castle Pinckney then it would be from quadrupling our force. The Charlestonians would not venture to attack this place when they knew that their city was at the mercy of the commander of Castle Pinckney. So important do I consider the holding of Castle Pinckney by the Government that I recommend, if the troops asked for cannot be sent at once, that I be authorized to place an Engineer detachment, consisting, say, of one officer, two masons, two carpenters, and twenty-six laborers, to make the rapiers needed there. They might be sent without any opposition or suspicion, and would in a short time be sufficiently instructed in the use of the guns in the cattle to enable their commander to hold the castle against any force that could be sent against it. If my force was not so very small I would not hesitate to send a detachment at once to garrisoned immediately if the Government determines to keep command of this harbor.

I need not say how anxious I am-indeed, determined, so far as honor will permit-to avoid collision with the citizens of South Carolina. Nothing, however, will be better calculated at prevent bloodshed than our being found in such an attitude that it would be madness and folly to attack us. There is not so much of feverish excitement as there was last week, but that there is settled determination to leave the Union, and to obtain possession of this work, is apparent to all. Castle Pinckney, being so near the city, and having no one in it bull an ordnance sergeant, they regard as already in their possession. The clouds are threatening, and the storm may break upon us at any moment. I do, the, most earnestly entreat that a re-enforcement be immediately sent to this garrison, and that at least two companies be sent at the same time to Fourth Sumter and Castle Pinckney-half a company, under a judicious commander, sufficing, I think, for the latter work. I feel the full responsibility of making the above suggestions, because I firmly believe that as soon as the people of South Carolina learn that I have demanded re-enforcement, and that they have been ordered, they will occupy Castle Pinckeny and attack this fort. It is therefore of vital importance that the troops embarked (say in war steamers) shall be designated for other duty. As we have no men who know anything about preparing ammunition, and our officers will be too much occupied to instruct them, I respectfully request that about half a dozen ordnance men, accustomed to the work of preparing fixed ammunition, be sent here, to be distributed at these forts.

Two of my best officers, Captain Seymour and Lieutenant Talbot, are delicate, and will, I fear, not be able to undergo much fatigue.