The immediate and direct operation of this act on the military peace establishment of 1815 was that of reduction, from which no officer belonging to it was exempt, unless it might be the topographical engineers; for in retaining the Corps of Engineers, as was manifest as well by the clear import of the section relating to it as by the provisions of every other clause of the act, reference was had to the organization, and not to the officers of the Corps. The establishment of 1815 was reduced from 10,000 to about 6,000 men. The 8 battalions of artillery, constituting what was called the corps of artillery, and the regiment of light artillery as established by the act of 1815, were to be incorporated together and formed into 4 new regiments. The regiments of infantry were to be reduced from 9 to 7, the rifle regiment being broken. Three of the general officers were to be reduced, with very many of the officers belonging to the several corps of the Army, and particularly of the infantry. All the provisions of the act declare of what number of officers and men the several corps provided for by it should thenceforward consist, and not that any corps as then existing or any officer of any corps, unless the topographical engineers were excepted, should be retained. Had it been intended to reduce the officers by corps, or to exempt the officers of any corps from the operation of the law, or in the organization of the several new corps to confine the selection of the officers to be placed in them to the several corps of the like kind then existing, and not extend it to the whole military establishment, including the staff, or to confine the reduction to a proportional number of each corps and of each grade in each corps, the object in either instance might have been easily accomplished by a declaration to that effect. No such declaration was made, nor can such intention be inferred. We see, on the contrary, that every corps of the Army and staff was to be reorganized, and most of them reduced in officers and men, and that in arranging the officers from the old to the new corps full power was granted to the President to take them from any and every corps of the former establishment and place them in the latter. In this latter grant of power it is proper to observe that the most comprehensive terms that could be adopted were used, the authority being to cause the arrangement to be made from the officers of the several _corps_ then in the service of the United States, comprising, of course, every corps of the staff, as well as of artillery and infantry, and not from the _corps of troops_, as in the former act, and without any limitation as to grades.