the United States, and it was not intended that you should make expeditions much beyond its borders without some great object of interest to the Federal Union to be suggested by you and approved here. Indeed, the thee-months' men were called into service mainly for defensive purposes, but permission would readily have been given to you to march into a neighboring State to countenance or to protect the friends of the Union, if you had presented a reasonable case for such interference. It is otherwise in respect to the greater of the long-term volunteers of your department when received, but as yet I am not aware that a single regiment has been presented or organized in your department. Out of these troops you will at the proper time replace the defensive posts occupied by the three-months' men, and hold the remainder in convenient camps of instruction-that is, near to wood, water, and cheap supplies, and to transportation by rail, canal, or river. It is suggested that these rendezvous or camps of instruction should consist of four or eight regiments each, and on ground either porous or slightly rolling. Larger camps soon exhaust the smaller supplies and comforts for too many miles around them. As a greater part of these troops are not expected to take the field much before the return of frost, they will, under good instructors, have ample time for the acquisition of tactical instruction and habits of discipline (obedience), without which they will not be equal to the expedition for which they are intended.
After desiring you to consult freely with the Governors of the States within your department on the best sites for these camps, I will here add a modifications of the expedition toward the Gulf of Mexico, alluded to in a former letter. I propose to organize an amry of regulars and volunteers on the Ohio River of, say 80,000 men, to be divided into two unequal columns, the smaller to proceed by water on the first autumnal swell in the rivers, headed and flanked by gun-boats (propellers of great speed and strength), and the other column to proceed as nearly abreast as practicable by land- of course without the benefit of rail transportation-and receiving at certain points on the river its heavier articles of consumption from the freight boats of the first column. By this means the wagon train the of the land column may no doubt be much diminished, but would still remain, I fear, so large as to constitute a great impediment to the movement. Would 80,000 men be sufficient to conquer its way to New Orleans and clear out the Mississippi to the Gulf? What should be the relative numbers of the two columns, and at how many points besides Louisville, Paducah, Columbus, Hickman, Memphis, Vicksburg, and New Orleans would the two columns be able to hold a close communication with each other? Of course much would depend upon the relations to the United States of Kentucky, Tennessee, and Missouri. I ask your views not only on the foregoing points, but also as to the form, draft, tonnage, and armament of the gun-boats or tugs. Cincinnati abounds in the best information on all these heads. Again assuring you that you are likely to bear an important if not be principal part in this great expedition, and of my great confidence in your intelligence, zeal, sciene, and energy, I remain, very truly, yours,
P. S. -Without waiting for the formal order of Secretary of War extending the limits of your department across the Ohio and the Mississippi, you will not hesitate to give any reasonable support (without comprosing your detachments) in your power to the friends of the Union in Kentucky, Tennessee, and Missouri.