WASHINGTON, July 8, 1807. SIR,--The Secretary at War having gone on to New York for the purpose of having that place put into a state of defence, your letter of July 4th to him has been put into my hands. I see with satisfaction that in an emergency too sudden to have been provided for by orders from hence, you have, under the guidance of your own judgment and patriotism, taken the measures within your power towards supporting the rights of your country. I will pray you to consider the proclamation of July 2d as laying down the rule of action for all our citizens, in their several authorities and stations; but that it is further desired of you to employ the means under your command, for defence of the country, its citizens, and property, against all aggressions attempted by the British armed vessels or other force. The Governor of Virginia being in a situation to act with more promptitude on any emergency which may arise, so far as respects the militia of the State, I have authorized and requested him to order into service such portions of the militia as he shall think necessary, on application from any of the persons charged with the defence of Norfolk or other places menaced. With him I recommend to you to communicate as to the militia to be employed, approving most myself whatever shall be most effectual for repelling aggression on our peace, and maintaining the authority of the laws. Accept my salutations, and assurances of great respect. TO THE HONORABLE THOMAS COOPER. WASHINGTON, July 9, 1807. DEAR SIR,--Your favor of June 23d is received. I had not before learned that a life of Dr. Priestley had been published, or I should certainly have procured it; for no man living had a more affectionate respect for him. In religion, in politics, in physics, no man has rendered more service.