Geordie lamp the base so that it gave more light and tried new versions on 4 and 30 November. This was presented to the Literary and Philosophical Society (Lit & Phil) of Newcastle upon Tyne on 5 December 1815. Although controversy arose between Stephenson's design and the Davy lamp (invented by Humphry Davy in the same year), Stephenson's original design worked on significantly different principles from Davy's final design. If the lamp were sealed except for a restricted air ingress (and a suitably sized chimney) then the presence of dangerous amounts of firedamp in the incoming air would (by its combustion) reduce
The Racecourse Colliery lamp' mines, i.e. the miners would have to make do with tallow candles set in a lump of clay. Mines were run on a day-to-day basis by the butty, this position can be compared to the modern-day contactor who would agree to sell coal to the mine owner at a fixed price. The butty would also hire and fire the men as required and at a pit like this, between six and 30 men could be employed. Every morning before the start of the shift the butty would go down with his safety lamp and check the workings for gases