R. Patterson, June 18, 1861

COLONEL: Finding, on my arrival here on the 15th instant, the enemy still in the vicinity of Martinsburg, I directed, in order to be able to carry out the original plan approved by the General-in-Chief, General Cadwalader, strongly supported, to cross the river at Williamsport and establish himself within the bend opposite and intrench himself. This was executed before I received the call for the regular troops with this column. It had, I think, the happy effect of causing the troops threatening Cumberland to retire.

That night, on receipt of the order from the General-in-Chief and direction to “keep within your [my] present limits,” I ordered the regular troops to be put in motion for Washington, and the volunteers brought back to this side, and in time for all to have returned by daylight. The execution of the order was deferred by the volunteers, and at night the inclosed report (No. 1)* was received from General Cadwalader. Presuming the enemy, who knows all our movements, had taken advantage of the withdrawal of the regulars to attack the remnant of two brigades, I at once turned Colonels Thomas and Miles, then here, to the support of General Cadwalader, and provided ample force to drive back any enemy in this vicinity. As soon as the force was on this side I detached the regular infantry, in compliance with the original order, for Washington. This fact I telegraphed to-day, and asked permission of the General-in-Chief to retain Thomas and Doubleday, the former too fagged to march, except under great necessity. The delay in returning that force to the General-in-Chief was at the time a necessity, and I feel confident he will pardon it.

The telegrams of the General-in-Chief indicate a desire for me not to advance beyond the Potomac. At present I cannot advance with any large force, as iny means of transportation are so limited. I should be

i as forced to halt every two days to send for supplies. To remedy many inconveniences, and to reopen the line of communication, and to protect the channels of trade, I propose what I consider a military necessity— the rebuilding of Harper’s Ferry Bridge, protected by a force from this side, and the reoccupation of Harper’s Ferry. For this purpose, and to fortify the heights in its vicinity, I wish the artillery under Doubleday. I would approach from this side, and would not think of marching on the right bank to Harper’s Ferry, exposed as my line would be for twenty miles to be cut at several points by the enemy; if not, to advance upon Winchester from this point or from Harper’s Ferry. I recommend this course if for no other reason than to keep the volunteers employed and out of settlements. From Harper’s Ferry at any time a force can be sent to you and to operate upon Winchester. I will remind the General-in-Chief that with the exception of one regiment (Connecticut) all this force will be entitled to discharge at the expiration of their three months, and I believe all but one regiment (the Wisconsin, an excellent one) will claim it. That force in Harper’s Ferry, open to the rear and fortified towards Winchester, can maintain itself. The railroad and canal will be reopened, and the people on the line encouraged to defend them.

I respectfully present the above to the consideration of the Generalin-Chiet, submitting to his superior judgment whatever his decision may be.

very respectfully, your obedient servant,