onsetter การใช้

The onsetter, Matthew Elliott, was the only man to have survived from the Busty seam and his evidence is quoted at length.
Wilkinson, John, 13 Oct 1846, aged 12, while standing waiting to be drawn up from the High Main Coal seam at Ludworth Pit on 13 October, John Wilkinson, aged 12, was accidentally knocked through a hole in the brattice by the onsetter, who was taking a tub out of the cage.
Brown, William Michael, 21 Feb 1902, aged 57, Master Shifter, deceased signalled to the winding engineman to take the cage from the 5 / 4 to main coal seam and then attempted to get into the cage, but the engineman, not knowing there was no onsetter there, dropped the cage at once, and Brown was caught and killed