On May 22, 1849, Congressman Abraham Lincoln received a patent for his method of lifting boats over shoals. The patent was granted when he was back in Springfield practicing law after one term as an Illinois congressman in Washington.
Lincoln labeled his invention Buoying Vessels Over Shoals. The invention consisted of a system of waterproof fabric bladders that could be inflated when necessary to help ease a stuck steamboat. When a ship got stuck or was at risk of hitting a shallow, the crew could activate the device which would inflate accordion-shaped air chambers along the sides of the watercraft to lift it above the water's surface, providing enough clearance to prevent the ship from getting grounded.
Lincoln’s idea 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.
Lincoln produced the scale model shown below with the help of Walter Davis, a Springfield mechanic. The model is now kept at the Smithsonian.
There is no evidence that the invention was ever put to practical use.
Lincoln remains the only U.S. president to have a patent in his name.
More on the story at www.smithsonianmag.com/… and en.wikipedia.org/...
Now let’s use our inventiveness to solve today’s puzzle composed in 1886 by British Chess composer Dr. Charles Planck (1856-1935). Planck was a mathematician and medical doctor and pathologist at the East Sussex County Asylum.
P.S.
The chess puzzle is published on Sundays, Tuesdays and Thursdays at 6:00 p.m. ET.
It is customary for advanced players to wait till midnight ET before posting the full solution. Before then, they provide some stats about the solution (e.g., the minimum number of distinct checkmate moves), help guide others, and sometimes post hints. But there are no hard-and-fast rules; feel free to post comments as you please.