the past three weeks, the power of the enemy being nearly doubled in men and heavy guns.

ZEALOUS B. TOWER,

Brevet Major, Chief Engineer, Department of Florida.

HEADQUARTERS DEPARTMENT OF FLORIDA,
Fort Pickens, May 27, 1861.

Lieutenant Colonel E. D. TOWNSEND, Assistant Adjutant-General:

COLONEL: Since my last dispatches no hostile movement has been made by the rebels, and we have been industriously employed in preparing to defend this fort, and have nearly completed the internal defenses, at least so far as we can do without sand bags. I have also completed and armed Batteries Lincoln and Cameron, the former with two 10-inch siege mortars and one 8-inch sea-coast howitzer, and the latter with two 10-inch columbiads. I am preparing beds for one 10-inch columbiad in the gorge of bastion D, and one in the salient of the counterscarp of bastion E. I have a gun for the former, and am daily expecting one for the latter, a schooner having three 10-inch columbiads, with projectiles, &c., having been spoken at Tortugas bound here. When she arrives I purpose erecting a battery of two guns on the point of the island south of the fort. I have established a camp about three-quarters of a mile from the fort, where the two infantry companies are encamped, and am cutting a military road in the interior of the island some three or four miles, to enable me, by prompt movements of the battery and other troops; to repel the enemy in case he makes a lodgment on it.

The schooner J. N. Genin will be unloaded probably to-morrow, it being very slow work in an open roadstead. These, I believe, are all my operations since I last wrote. I see by the Herald of the 4th instant that Captain Meigs reports this fort as being secure from all possible attacks, and able to resist any that can be made against it. If Captain Meighs has made such a report he has reported what at the time was notoriously incorrect, and his report has been very injurious by probably preventing those supplies of arms and ammunition which are of vital importance, and which would doubtless have been promptly sent had our real condition been correctly reported, but which, of course, would not be to a fort able to resist any attack that could be made on it. At the time Captain Meighs left here this fort was in no condition for offense or defense. Every gun, every front, and every casemate but one was unprotected, and open tot he shot and shells of the enemy, and their defense must have been at a fearful loss of life. There were only two 10-inch columbiads mounted-the only guns that can with certainty and efficiency reach the enemy-and there were not shells enough either of columbiads, howitzer, or mortar for one half day's firing, nor have I now enough to last, even with moderate firing, more than four days; and the only guns in the fort to be depended on are the columbiads, though I hope and believe I can reach the enemy with the 32-pounders, the howitzers, and the mortars.

I send you a sketch [inclosure I], by which it will be seen how we are surrounded, and that most of the batteries are beyond the ordinary range of our guns. It must always be borne in mind that the armament of this fort was designed to reach only to the channel. We, I trust, now will be able to defend ourselves against the enemy. We