you will probably remain but a short time at Centralia and Renick no particular arrangements will be required for quarterin your men; tents, barns, and unoccupied buildings may be taken for this purpose. The object of this expedition being an important one, you will be promt and vigilant in the execution of these instructions. You will keep these headquarters advised by telegraph of all your movements, and will report fully by mail. In regard to taking prisoners and seizing property, you will be governed by General Orders, Numbers 8 and 13, of this department.

Additional instructions will probably be given you soon after your arrival at your destination.

Very respectfully, &c.,

H. W. HALLECK,

Major-General.

SAIN LOUIS, Mo., December 11, 1861.

Brigadier General T. H. McKEAN, Jefferson City, Mo.:

GENERAL: You will receive this to-morrow evening. In the mean time you will receive instructions to have the Eleventh Iowa Regiment on board a steamer for transportation up the river. The destination of that regiment is Providence, at which place it will land, and immediately proceed to capture or disperse a band of rebels said to be assembled at Columbia. Having accomplished this object, it will proceed direct, or by Rochefort or Booneville, to Fayette, for the same purpose, and thence to Glasgow and Brunswick.

General Pope will probably send a force across from Booneville to Fayette, to co-operate with the Eleventh Iowa. A regiment has been dispatched to Centralia and Renick, to operate south against Columbia and Fayette, to intercept any of the enemy moving from these places towards the North Missouri Railroad.

The steamer sent with the Eleventh Iowa will remain at Providence till the result of the expedition to Columbia is known, to carry the troops to Rochefort or Booneville, or will be permitted to proceed up the river to those places and Glasgow, as you may deem advisable. It is supposed that from your position you will be better able to judge of the rebel forces at the places named than can be done here. As the expedition will move but a short distance on land they will require but little transportation-say five or six wagons-and provisions of only six or eight days. Additional supplies should be put on the boat, which, if not wanted, may be landed and turned over to the proper officers at Booneville. The four companies of cavalry which you will receive to-morrow afternoon will be sent in another steamer to Providence, Rocherfort, or Booneville, to co-operate with the Eleventh Iowa. All these forces should be well supplied wiht ammunition. You will keep me informed by telegraph of the movement of these forces.

If steamer should not be able to ascend the river to Providence the expedition should croos the river at Jefferson City and march by land to Columbia. In this case a larger amount of transportation should be given. It is supposed that a portion at least of supplies and forage may be procured in the country passed over. In regard to taking prisoners and private property, strict compliance with General Orders, Nos. 8 and 13, of this department, will be required.