Franklin Roosevelt actually said...
By virtue of the authority vested in me by section 1 of the act of July 9, 1918, c. 143, 40 Stat. 845, 848, it is ordered that all the public land within the following-described area be, and it is hereby, withdrawn from all forms of appropriation under the public land laws.
Context
Executive Order 8579—Withdrawal of Public Land for Use of the War Department as an Aerial Bombing and Gunnery Range
10/28/1940