Gen. Jos. E. Johnston has written from the West a gloomy letter to Mr. Wigfall, Texan Senator. He says he is ordered to reinforce Lieut.-Gen. Pemberton (another Northern general) from Bragg’s army. Pemberton is retreating on Grenada, Mississippi, followed by 40,000 of the enemy. How is he, Gen. J., to get from Tennessee to Grenada with reinforcements, preceded by one army of the enemy, and followed by another?

Mr. Wigfall recommends the Secretary (as if he could do it!) to concentrate all the armies of the West, and beat the enemy out of the Mississippi Valley. Gen. Johnston says Lieut.-Gen. Holmes has been ordered to reinforce Pemberton. Why, this is the very thing Mr. Randolph did, and lost his clerkship for it! The President must have changed his mind.

Gen. Randolph sent in his resignation as brigadier-general to-day. The younger brigadiers, Davis (the President’s nephew) and Pryor, have been recently assigned to brigades, and this may have operated on Randolph as an emetic.

There are two war steamers at Charleston from abroad; one a Frenchman, the other an Englishman. Gen. Beauregard entertained the officers of the first the other day.

Gen. Banks has sailed down the coast on an expedition, the nature of which, no doubt, will be developed soon.

December 11th.—Gen. Lee dispatched this morning early that the enemy were constructing three pontoon bridges, and that firing had commenced on both sides. At nine o’clock a.m. the firing increased, and Gen. Lee dispatched for ammunition, looking to the contingency of a prolonged battle.

At three p.m., Gen. Lee says, the enemy had been repulsed in two of their attempts to throw bridges over the river; but the third attempt would probably succeed, as it was under cover of batteries which commanded the river, and where his sharpshooters could not reach the workmen. But, he says, his batteries command the plain where the enemy must debouch. We may speedily hear of a most sanguinary conflict.

Burnside must have greatly superior numbers, or else he is a great fool to precipitate his men into a plain, where every Southern soldier is prepared to die, in the event of failure to conquer! There is no trepidation here; on the contrary, a settled calm on the faces of the people, which might be mistaken for indifference. They are confident of the success of Lee, and really seem apprehensive that Burnside will not come over and fight him in a decisive battle. We shall soon see, now, of what stuff Burnside and his army are made. I feel some anxiety; because the destruction of our little army on the Rappahannock might be the fall of Richmond.

It is rumored that the President started two days ago for the West—Tennessee and Mississippi. No papers have been sent in by him since Tuesday, and it may be true. If so, he means to return speedily. I think we shall soon have news from the lower James River.

A letter from the Governor of Alabama calls urgently for heavy guns, and a reserve force, for the defense of Mobile.