NMAH/SI Upon hearing the name Abraham Lincoln ... half dozen or so most valuable things in our collection." Lincoln's patent, No. 6,469, was granted on May 22, 1849, for a device for "Buoying ...

Abraham Lincoln! He is the only US president to ... who was himself something of a mechanic…." Unfortunately, Patent No. 6,469 was never tested for its viability, and there is some skepticism ...