The doorknob was invented in 1878 by Osbourn Dorsey when he filed a patent for an internal mechanism that latched doors shut. If Dorsey's knob was on the left side of a door, it unlatched a metal bar on the right side of the door.Know More
The metal rod latched into a hole in the door frame. Homeowners accessed the connection in the frame by unscrewing a small metal cover.
Before doorknobs, homeowners secured doors by using a latch string that looped around a bar to keep strangers out. In ancient times, people raised and lowered bars to secure doors so that people could not get inside.Learn more about Inventions
Mary Phelps Jacob, a New York socialite, received a patent for the "Backless Brassiere", the precursor to the modern bra, on Nov. 3, 1914. She created it using two handkerchiefs and a ribbon after buying a sheer evening dress that was unsuitable for wearing with a whalebone corset.Full Answer >
Otis Boykin invented the resistor, and he received a patent for it on June 16, 1959. Boykin was an electronic scientist and inventor who lived from 1920 to 1982. He held a total of 26 patents when he died, having invented other significant devices, such as a control unit for pacemaker machines.Full Answer >
Richard Arkwright and John Kay of Great Britain invented the water frame in the late 1760s, and Arkwright applied for a patent in 1769. The patented spinning machine twisted 96 strands of yarn simultaneously.Full Answer >
Peter Cooper Hewitt became the inventor of the first fluorescent lamp when he was awarded a patent in 1901 for his low-pressure mercury vapor lamp. The first high-pressure mercury vapor lamp, invented by German-born Edmund Germer, Friedrich Meyer and Hans Spanner, was patented in 1927.Full Answer >