[440]

Inventions
Jefferson invented many small practical devices and improved contemporary inventions, including a revolving book-stand and a "Great Clock" powered by the gravitational pull on cannonballs. He improved the pedometer, the polygraph (a device for duplicating writing),[441] and the moldboard plow, an idea he never patented and gave to posterity.[442] Jefferson can also be credited as the creator of the swivel chair, the first of which he created and used to write much of the Declaration of Independence.[443] He first opposed patents and later supported them. In 1790–1793, as Secretary of State, he was the ex officio head of the three-person patent review board (the Secretary of War and the Attorney General being the other two patent reviewers). He drafted reforms of US patent law which lead to him being relieved of this duty in 1793, and also drastically changed the patent system.[444]
As Minister to France, Jefferson was impressed by the military standardization program known as the Système Gribeauval, and initiated a program as president to develop interchangeable parts for firearms. For his inventiveness and ingenuity, he received several honorary Doctor of Law degrees.