On April 6, 1858, Abraham Lincoln delivered his lecture on “Discoveries and Inventions” before the Young Men's Association of Bloomington, Illinois. Throughout the year, he gave the lecture four more times in Illinois towns. His law partner, William H. Herndon, explained, “He began preparation in the usual way by noting down ideas on stray pieces of paper, which found a lodgment inside his hat, and finally brought forth in connected form a lecture.” Lincoln was highly interested in inventions. Ten years earlier, he received a patent for an invention that lifted boats over shoals. Herdon claimed that Lincoln stopped giving the lecture because it was not well received. Five presentations in a fairly short time call that notion into question. Lincoln last presented “Discoveries and Inventions” just five days before his memorable Cooper Union address. It seems more likely that the celebrated New York City speech provided a robust launch for Lincoln’s presidential campaign, and that h...