JACKSON, MISS., December 14, 1861.

His Excellency JEFFERSON DAVIS,

President, Richmond:

DEAR SIR: I am earnestly requested by the people of the Mississippi Gulf coast and by Governor Pettus to ask the attention of the President and the Secretary of War to the defense of the coast by a military force on shore sufficient to protect property and repel invasion by the enemy. The governor requests me to ask that three regiments shall be accepted for local defense, to be stationed on the coast; also a battalion which he has now organized and equipped, and which could be sent there immediately. It is also requested by him and by the Honorable R. Seale, Representative from the coast, that the Third Regiment, Colonel Deason's, shall be one so accepted, and that it be ordered back tot he coast, from which it was by recent order of General Johnston removed to Columbus, Ky., where it now is. The reason for this is that this regiment is composed mainly or in large part of men familiar with the coast, its bays and bayous, and accustomed to the management of water-craft. This is very important, and the governor authorizes me to say he will supply its place at Columbus with another regiment at the earliest practicable day. The legislature has made an appropriation of $ 250,000 to build gunboats on the coast, and force will be required to protect the points at which they are to be constructed. The necessity of a military force for our coast protection and defense is imperious, and I earnestly and respectfully urge it upon the President and Secretary of War.

Most respectfully, your obedient servant,

JOHN J. McRAE.

The Seventh Regiment, Colonel Goode's, is now upon the coast at Bay Saint Louis and in the Confederate service, under command of General Lovell. This to be one of three.

HEADQUARTERS DEPARTMENT Numbers A, New Orleans, La., December 16, 1861.

Honorable J. P. BENJAMIN,
Secretary of War:

SIR: I have the honor to acknowledge the receipt of yours of the 7th instant, inclosing a letter from Dr. Cartwright to the President, relative to the Mexican Gulf Railroad. I am not aware that the Government or the parties who claim to have purchased the road have any intention of using the iron for ship-building purposes, nor do I believe that any such purpose exists. Had any plan of that railroad been laid before me, I should have weighed the respective advantages go the Government of using the iron on the road or on the ships and decided accordingly. I am well satisfied that the whole scheme is to make a grand speculation for private purposes, either by seedling the iron in this market or by forcing the road upon the Government at an exorbitant price.

I have a work at Proctorsville, across the railroad, mounting six 32-pounders, and manned by 100 men, distant from the city 27 miles, which covers the valuable plantations along the left bank of the river. To re-enforce this work rapidly I have constructed a switch from the Pontchartrain to the Mexican Gulf road, at a cost of &1,600, and am putting up telegraph lines between the city and Proctorsville, which