That in case of vacancy in the office of Secretary of State, Secretary of the Treasury, or of the Secretary of the Department of War, or of any officer of either of the said Departments whose appointment is not in the head thereof, whereby they can not perform the duties of their respective offices, it shall be lawful for the President of the United States, in case he shall think it necessary, to authorize any person or persons, at his discretion, to perform the duties of the said respective offices until a successor be appointed or such vacancy be filled: _Provided_, That no one vacancy shall be supplied in manner aforesaid for a longer period than six months. It is manifest that if the power which this law gives had been withheld the public interest would frequently suffer very serious detriment. Vacancies may occur at any time in the most important offices which can not be immediately and permanently filled in a manner satisfactory to the appointing power. It was wise to make a provision which would enable the President to avoid a total suspension of business in the interval, and equally wise so to limit the Executive discretion as to prevent any serious abuse of it. This is what the framers of the act of 1795 did, and neither the policy nor the constitutional validity of their law has been questioned for sixty-five years. The practice of making such appointments, whether in a vacation or during the session of Congress, has been constantly followed during every Administration from the earliest period of the Government, and its perfect lawfulness has never to my knowledge been questioned or denied. Without going back further than the year 1829, and without taking into the calculation any but the chief officers of the several Departments, it will be found that provisional appointments to fill vacancies were made to the number of 179 from the commencement of General Jackson's Administration to the close of General Pierce's. This number would probably be greatly increased if all the cases which occurred in the subordinate offices and bureaus were added to the count. Some of them were made while the Senate was in session; some which were made in vacation were continued in force long after the Senate assembled. Sometimes the temporary officer was the commissioned head of another Department, sometimes a subordinate in the same Department. Sometimes the affairs of the Navy Department have been directed _ad interim_ by a commodore and those of the War Department by a general. In most, if not all, of the cases which occurred previous to 1852 it is believed that the compensation provided by law for the officer regularly commissioned was paid to the person who discharged the duties _ad interim_. To give the Senate a more detailed and satisfactory view of the subject, I send the accompanying tabular statement, certified by the Secretary of State, in which the instances are all set forth in which provisional as well as