Samuel Colt was notable for his revolutionary thought of revolvers. Thus, every 25th of February is set aside to celebrate Pistol Patent Day, in commemoration of the origin of the first revolver. Back in 1835 in Europe and 1836 in the U.S., Samuel Colt had his revolver design patented. His patent number was #138.
It was he, who invented pistol with a chamber that could hold six bullets at a time. It was a chamber that would merely revolve by itself for changing the bullets. His design was an avant-garde. He thought of a pistol with all parts detachable. He was targeting to create a gun through machinery, and not via manual handling production.
That revitalized the gun manufacturing industries, as pistol making was made easy by this innovative concept. Thus, should anyone want to get his designed firearm patented, and then this day is the best time to implore for such.