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Description, with Drawing^ of a Self- Acting Stopper for Wind- 

 ing-Engines. By Mr John Maxton, F.R.S.S.A., Engineer, 

 late of Greenock, now of Leith. (With a Plate.) Communi- 

 cated by John Scott Russell, M.A., F.R.S.E., F.R.S.S.A.* 

 Communicated by the Royal Scottish Society of Arts. 



My attention having been directed to the numerous acci- 

 dents which occur in consequence of Winding-engines at coal-pits 

 being left in charge of careless engine-men, I designed the ap- 

 paratus, represented in Plate II, to be attached to the gearing 

 of the engine, so that, independent of the engine-man, the ma- 

 chinery would stop when the tub or bucket had reached its 

 proper height. 



In fig 1, A is the fly-wheel shaft of engine, on which is fixed 

 a bevelled pinion B, which works the wheel C, into the eye of 

 this wheel a screwed rod J moves, having an oblong hole D 

 at the opposite end ; V is the eccentric rod, E is the double 

 hand-gear crank, is part of the fly-wheel, 7? is a friction- 

 strap, F is a lever with a heavy ball of metal on the upper 

 end, G is a link connected to the eccentric rod. In this link a 

 pin, fixed in a lever H, is made to move freely, so that when the 

 edge of the oblong hole D comes in contact with the ball-lever 

 F, it will throw it either way, according to the direction in 

 which the engine and screwed rod J moves ; when the lever F 

 falls, it will tighten the friction-strap on fly-wheel, and throw 

 the eccentric rod out of gear ; by the pin in the lever H acting 

 on the top, or under side of link G. The reason why the link is 

 long, is to allow the crank and pin H to travel (by the screwed 

 rod in wheel), without moving the eccentric rod out of gear, 

 till it arrives at either top or bottom of link, which is the proper 

 time that the engine should be stopped, the tubs being then 

 at the proper height. A handle is attached to the shaft K, for 

 the purpose of allowing the engine-man to take the strain off* 

 the friction-strap to let the engine get under way. Figs. 2, 



* Read before the Royal Scottish Society of Arts 24th January 1842. Re- 

 port of Conunittee read and approved 13th June 1842, and the Society's Silver 

 Medal, value Ten Sovereigns, awarded 14th November 1842. 



