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
Safety lamp the Stephenson lamp was easily broken, and allowed the flame to ignite firedamp in the mine. Later Stephenson designs also incorporated a gauze screen as a protection against glass breakage. Developments, including the Gray, Mueseler and Marsaut lamps, tried to overcome these problems by using multiple gauze cylinders, but glass remained a problem until toughened glass became available. Were the flame to go out in a lamp, then there was a temptation for the collier to relight it. Some opened the lamps to light tobacco pipes underground. Both of these practices were strictly forbidden; they clearly negated the whole point