United States patent number 6,469 is for "buoying vessels over shoals." Granted on May 22, 1849, the concept involves equipping large boats with "india-rubber cloth, or another suitable waterproof fabric" on the hull as inflatable floats. If a boat became stranded, these buoys could be inflated with air to lift it in the water and set it free. Who had this bright idea?
Abraham Lincoln! He is the only US president to hold a patent.
From Smithsonian:
[Lincoln's inspiration] came as a result of river and lake expeditions he made as a young man, ferrying people and produce on the Mississippi and the Great Lakes[…] According to Harry R. Rubenstein, chair of the Division of Politics and Reform at NMAH, Lincoln "was keenly interested in water transportation and canal building, and enthusiastically promoted both when he served in the Illinois legislature." He was also an admirer of patent law, famously declaring that it "added the fuel of interest to the fire of genius."Lincoln appears to have had more than a passing affinity for mechanical devices and tools. William H. Herndon, his law partner at the time he was working on his invention, wrote that Lincoln "evinced a decided bent toward machinery or mechanical appliances, a trait he doubtless inherited from his father who was himself something of a mechanic…."
Unfortunately, Patent No. 6,469 was never tested for its viability, and there is some skepticism about whether it's a practical solution. Meanwhile, the original patent application is missing a key component: Lincoln's original signature appears to have been sliced out of the document, most likely by an autograph collector or reseller.
Previously:
• I searched Google Patents for the toilet paper patent
• Expired patent of the day: Lego
