William McKinley actually said...

Now, therefore, I, William McKinley, President of the United States, by virtue of the power in me vested by section ten of said act of March...

As other portions of the enemy's territory come into the possession of the land and naval forces of the United States, postal communication ...

The Postmaster-General is charged with the execution of this order in co-operation with the military commander, to whom the Secretary of War...

The revenues derived from such service are to be applied to the expenses of conducting it, and the United States postage stamps are therefor...