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
Kerosene lamp of combustion lighting are a continuing concern in many countries. Flat-wick lamps have the lowest light output, center-draft round-wick lamps have 3–4 times the output of flat-wick lamps, and pressurized lamps have higher output yet; the range is from 8 to 100 lumens. A kerosene lamp producing 37 lumens for 4 hours per day consumes about 3 litres of kerosene per month. 12.57 lumens = 1 CP Kerosene lamp A kerosene lamp (also known as a paraffin lamp in some countries) is a type of lighting device that uses kerosene (paraffin) as a fuel. Invented by the Polish pharmacist Ignacy