He explained that lightning followed the same principles as the sparks from Franklin's electrostatic machine. Poggendorff is known for his electrostatic motor which is analogous to Wilhelm Holtz's electrostatic machine. The electrical principles of Corbett's electrostatic machine were later used by Edison. Eighteenth-century scientific laboratories usually contained some form of hand-operated electrostatic machine. In the 1830s, Georg Ohm also constructed an early electrostatic machine. W. R. Pidgeon developed the "Pidgeon machine", an electrostatic machine with a unique setup. These also drove an electrostatic machine to generate the electricity to power the syphon. At age ten, he built an electrostatic machine that he used to shock his friends. Thomas Penn, son of William Penn, made an electrostatic machine that supplemented Collinson's equipment.