Engineer (1890–1974) known for his pivotal role in the development of the atomic bomb as a primary organizer of the Manhattan Project. Vintage fountain pen signature, “Vannevar Bush,” on an off-white 6 x 1.75 slip. Slip is affixed to an 8.5 x 11 album page with an affixed clipped photo and biographical information. Area of light toning from show-through from adhesive on reverse, otherwise fine condition. RRAuction COA.