History of chemistry iodine first, but both scientists acknowledged Courtois as the first to isolate the element. In 1815, Humphry Davy invented the Davy lamp, which allowed miners within coal mines to work safely in the presence of flammable gases. There had been many mining explosions caused by firedamp or methane often ignited by open flames of the lamps then used by miners. Davy conceived of using an iron gauze to enclose a lamp's flame, and so prevent the methane burning inside the lamp from passing out to the general atmosphere. Although the idea of the safety lamp had already been demonstrated by
Tensor lamp Tensor lamp Tensor lamp is a small high-intensity and low-voltage desk lamp invented by Jay Monroe. The lamp was mainly popular during the 1960s and 1970s. The lamp was originally used by doctors and dentists, and later became more widely used. The first Tensor lamp consisted of assembling together a 12-volt automobile parking light bulb and reflector made from an ordinary kitchen measuring cup. Monroe fixed the cup to a metal tube that was attached to a transformer, which reduced 115-volt house current to 12 volts. Because of the small bulb, the entire lamp could be made smaller with a