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Re; Raises When I was working at the Mosaboni copper mine, in Bihar, India, in 1958-60, the vertical interval between successive levels was 120 feet. Mostly the raises put up in the vein were inclined at about 40 degrees, but a series of ore transfer raises we put in were inclined at 60 degrees. As in the case of other raises which have been described, access up the raise was by steel rope ladder, set to one side. The "working platform" from which the round was drilled consisted of two planks of wood supported on two short drill steels inserted in holes drilled into the footwall. Barring down of loose rock, and construction of the stage was done by "timbermen" on the morning shift. When I was on morning shift and on my second round of the section of which I was shift boss, my job would include marking up the round to be drilled in the afternoon shift. When I was on afternoon shift, I would inspect the round which had been drilled, and agree with the drillers if they needed to put in an extra hole -- sometimes they could not drill exactly to the pattern required. The raise drillers were all Gurkhas, drilling with hand-held Holman drills, without benefit of air-legs. The drilling machines were pushed up by shear strength. All blasting was done on the night-shift by Indian blasters under the supervision of an Indian foreman, using safety fuse of (hopefully!) adequate length to allow the blaster time to climb down. One of the English staff at the mine, a mine-captain engaged as a "master driller", told me that his previous job had been to operate a one-man fluorspar mine in Derbyshire. He liked living dangersously, and told me with pride of how he had put up vertical raises without ladders -- he just had an array of old drill steels stuck in holes in the side walls, and scrambled down these quickly after lighting the fuses! The latest way to make a raise, of course, is to use a raise-boring machine. This sits in the upper level, and first drills a hole of about eight to twelve inches diameter down to the lower level. Once this has been done, a reaming head is fitted to the drill string at the lower level, and the machine then reams to hole out from the bottom upwards, up to about eight feet in diameter at a single pass. The commonest make of raise-boring machine is Robbins, and in Mexico, where all raises are now made in this way, the modern name for a raise is "Un Robbins". At one mine I visited in 1986, an underground vertical shaft consisted of two parallel Robbins- bored raises, with one cage in each. The latest development of the Kiruna iron ore mine in Sweden, which involved the construction of several major deep-level ore-passes was also carried out using Robbins raise-borers, the diameters of the initial raises being slashed out by drilling radially outwards from a suspended stage within the raise. Tony Brewis stage the lower level his previous %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%