an experienced officer of the Ordnance Corps, while another will be required to superintend the issue, care and repairs of arms and ammunition. Whenever the necessities of defense at Washington, &c., will justify it, I will be glad to have McCook's and Wilson's regiments (First and Second Ohio, now at Harrisburg or Lancaster) ordered back here, if you intend my command to operate on the Ohio line. I am particularly anxious for the former, on account of the character, of its colonel. I propose, until receiving orders from you, to establish my command in a camp of instruction at some point near Cincinnati where I can reduce them to order as soon as possible. Until I hear from you I will consider it my duty to take all possible measures for the protection of Cincinnati and the line of the Ohio within this State. I will obtain all the information possible in relation to the ground opposite Cincinnati on the Kentucky side, and without attracting attention take all the steps necessary to occupy the heights when the proper moment arrives. I will be careful to do nothing that can compromise the Government in any way with the inhabitants of Kentucky. I will take steps, by the use of secret-service money, to obtain early information as to any hostile movement from the South. I would be glad to be furnished with a cipher.

A few heavy guns and howitzers will be essential at Cincinnati in case it should become necessary to occupy the heights on the opposite side, or to silence the fire of hostile batteries. I would for the present ask, for say, twelve 24-pounders, six 8-inch howitzers, six 12-pounderse, two 8-inch mortars, two 10-inch mortars, with the requisite implements and ammunition. We can very soon cast our own shot and shell if necessary. We need at least one light battery, and I will do what I can to organize one or more while awaiting your further orders. A force of cavalry will also be required for patrol duty. I make these suggestions on the supposition that it will, for the present at least, be may duty to provide for the defense of the frontier. It would be well that I should have some understanding with the commanding officer of the Indian troops by which a movement on Louisville could be made should it become necessary in order to relieve a pressure on Cincinnati. If I am correct in supposing that for the present my command is to be kept together and charged with the defense of Ohio, or a movement in advance should political events require it, I would recommend that it be formed into a corps d'armee, and provided with suitable batteries and cavalry force. A battalion of regulars would be of great assistance in the event I speak of. I would urge the immediate dispatch of the staff officers I have asked for. You can imagine the condition in which I am without a single instructed officer to assist me. I telegraphed to-night to General Harney asking him to lend me Captain Dickerson for a few days. I would suggest that Lieutenant Poe, now at Detroit, would be of great use to me. I will take steps to secure the safety of the Ohio railways, and will make such arrangements with their managers as will enable me to control all their resources. I beg, general, that you will excuse the hurried nature of this report.

I am, very respectfully, your obedient servant,

GEO. B. McCLELLAN,

Major-General, Ohio Volunteers.

I omitted asking for a medical director to organize the hospital and ambulance service.

[2.]