. Transactions of the Institution of Mining Engineers . the molten tip of the electrode with aprotective coating. In all high-voltage methods of wielding it is possible to draw out toolong an arc; in fact, unless the operators hand be miraculously steady,such occasional over-lengthening of arc is bound to occur. The result isthat the nature is burnt out of the molten beads at the electrode tip,and the beads inevitably oxidize in their passage through the long arc,resulting in a slagged deposit lacking in all the essential properties of areliable weld. The coated electrode is an attempt to mini
. Transactions of the Institution of Mining Engineers . the molten tip of the electrode with aprotective coating. In all high-voltage methods of wielding it is possible to draw out toolong an arc; in fact, unless the operators hand be miraculously steady,such occasional over-lengthening of arc is bound to occur. The result isthat the nature is burnt out of the molten beads at the electrode tip,and the beads inevitably oxidize in their passage through the long arc,resulting in a slagged deposit lacking in all the essential properties of areliable weld. The coated electrode is an attempt to minimize this effect. Owing to the low^ voltage of the Wilson system and the automaticcontrol through the solenoid-operated resistance, the current is cut off thearc at a predetermined length well under the safety limit, and varyingin accordance with the composition of the electrode in use at the time, nosuch burning or oxidation being possible. The further discussion of the paper was adjourned. THE [fenARYOF THEUNIVERSITY Of ILLINOIS Vol. LXIL, Plate 1921-1922.] RHODES PRESIDENTIAL ADDRESS. 141 THE MIDLAND INSTITUTE OF MINING, CIVIL, ANDMECHANICAL ENGINEERS. GENERAL MKETING,Held at the South Grove Secondary School, Moorgate, Kotherham,October 22nd, 1921. H. RHODES, President, in the Chaik. DEATH OF SIR WILLIAM GARFORTH, The President : I deeply regret that my first official duty is a very•sad one, and one that has become only too common during the lasteighteen months or more. I refer to the death of Sir William Garforth,whose works as a mining engineer are well known to all present, so thatI need not enlarge on them. Wherever coal-mining is practised, thename of Sir William Garforth is known, chiefly from his researches intothe question of the use of stone-dust in preventing the spread of explo-sions, and also from the fact that he was one of the pioneers in theintroduction of mechanical coal-cutters into South Yorkshire, if not intothe United Kingdom. In pro
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Keywords: ., bo, bookcentury1800, bookdecade1890, booksubjectmineralindustries
