Denton, Greater Manchester and then abandoned. After hatting, the most important industry in Denton was the manufacture of lead-acid batteries by Oldham Batteries (Oldham & Son Ltd). In 1865, Joseph Oldham established a millwright general engineering shop and by 1887 this company was manufacturing machinery for the hat-making industry. Another important industry in the area was coal mining and shortly after 1887 the company began making machinery and equipment for this industry, which included miners' portable lamps. Up to this time, miners had always used the safety lamp devised in 1815 by Sir Humphry Davy (1778–1829) but this new battery-powered Davy lamp eventually
Cap lamp that the LEDs improved hazard detection. Cap lamp A cap lamp is a lamp worn on the head or helmet. It is mostly used in an underground environment, like mines or during outdoor activities, e.g. climbing. A patent for a self-adjusting bracket for use with cap lamps was awarded in 1985. The two most recent variants of the cap lamp are the GEN 4 and GEN 5 models. The GEN 4 model, approved for use by the Mine Safety and Health Administration (MHSA), uses the headpiece of existing cap lamps, but retrofitted with new LEDs and electronics. The GEN 5