The basic method employed in this percussion method of drilling was to suspend nearly two tons of drilling tools at the end of a heavy manila rope or cable, and allow the chisel bit to crush the rock at the bottom of the hole. If the rock did not collapse into the hole, it could be taken to quite a depth without benefit of a well casing. Most often, however, rock cuttings were suspended in a muddy fluid at the bottom and had to be pumped or "bailed" out via a hollow pipe with a valve at the bottom end. The cable-tool or "jar head" method of drilling was gradually abandoned in favour of the rotary or "swivel-neck" method, introduced about 1930 (see illustration 20). Subsequently, the cable-tool rig was only used for "spudding in," that is, for commencing the drilling of a new well or for drilling very shallow wells.
The size of the cable-tool rig was usually determined by the size of the rig-irons and the diameter of the crank-shaft, ordinarily 15 centimetres. It also consisted of a "walking beam," like that of the earlier spring-pole rig (see Canada's Visual History, volume 56, illustration 6), for raising and dropping the drilling tools. It had bailing equipment for lifting out rock cuttings, and a series of spools: "bull-wheels" on which were wound drilling lines such as the mania rope on the floor in the background; and "calf-wheels" on which were wound the wire cable (held on the left) for raising and lowering pipe casing (to the right of cable). The equipment itself was carried by a wooden derrick built on location with simple hand tools such as a cross-cut saw, hatchet and foot adze. Operating twenty-four hours per day, the rig shown here took two years to drill to a depth of 825 metres. Two shifts of two men, the driller (Martin Hovis, left, or William Elder) and the tool dresser (Bob Brown, right, or another unidentified man), each worked a twelve-hour tour. The driller ran the rig, monitored the controls, and supervised operations such as hoisting the pipe (shown here), while the tool-dresser generally assisted about the rig, cleaning and repairing machinery, heating and dressing worn bits, and firing and maintaining the steam boiler.
Courtesy: Provincial Archives of Alberta, H. Pollard Collection (P 1303)