tonnage of smelted lead that ore had produced (thus, a "tontale"). The individual miner's family also contributed; the sons worked on the uncovered washing platforms (exposed to the elements in all weathers) washing the impurities from the ore prior to smelting, and the wives and daughters spun wool and embroidered muslin for sale in Glasgow. The partners supplied their own tools; and were responsible for their upkeep. Many important responsibilities lay with the partners; thus, for instance, only two overseers were needed to manage more than 200 Leadhills’ miners. In the absence of an overseer's constant and immediate personal supervision, the partners were totally responsible for their collective work practices and occupational safety; thus, the partners, rather than overseers, would decide how to act against threats posed by subterranean water, loose ground, earth tremors, etc. However, with no overseer, there was also no oversight; and, often, hastily constructed passages/shafts were misaligned with those of other teams, affecting the structure of the entire mine—also, the disposal of waste and rubbish from one team's work area often impeded the progress of another team (or teams). Steam engines Coal-fired steam engines, were an important part of the operation at Leadhills. Leadhills had three steam engines as early as 1778 (Smout, 1967, p. 106). In the winter of 1765, James Watt had been approached to design and build a steam engine for Leadhills that would raise water from 30 fathoms (approx. 55 m) below the surface. Watt did not get the contract (Hills, 1998). 1817 mining accident According to his later report (Braid, 1817), at 7:00am on 1 March 1817, the mine's surgeon, James Braid, was called urgently to the mine to alleviate the distress of a number of miners who appeared to be suffocated. It was later established that noxious fumes from the faulty chimney of a coal-fired steam engine, operating deep within the mine, had combined with a dense fog pervading the entire area. The contaminated air was lethal. Two men, in the hope of finishing early, and contrary to established Leadhills custom, had entered the mine before 4am; another two, presumably from the same partnership, entered soon after. Reaching their work level (at 25 fathoms) the first two encountered the bad air. They persisted, thinking they could force their way through it, began to feel dizzy, collapsed, and eventually suffocated. The next two encountered a similar fate. The accident was not