Inventions, Discoveries and Explorations

Abraham Lincoln is the only US president to have a registered patent for his invention. On March 10, 1849, he filed a patent for a device that would help ships float over shallow areas of water. The patent was approved two months later as Patent No. 6,469.

The answer is Dr. Charles H. Townes. He is an American physicist and engineer who is best known for his work on the maser and laser. In 1954, he developed the maser, a device that amplifies microwaves using stimulated emission. In 1960, he was one of the inventors of the laser, a device that amplifies light using stimulated emission. Townes shared the 1964 Nobel Prize in Physics with Nikolai Basov and Alexander Prokhorov for their work on the development of the maser and laser.