3 8 Of the Under 'ground hic lined Plant , ^e, 



loaded boat going down, and an empty boat going up the 

 iinder-e;round inclined plane. G, a brick wall from the fole 

 to the top of the inclined plane, in order to give additional 

 fnpport to the roof, h hh h, openings through the brick, 

 \vall G, into which n perfon may ftep out of the way of the 

 boats, at the time they are paffing lip and down, i/a bell, 

 which IS rung by the rope dotted to b, upon the lower level, 

 ;^t the bottom of the undfer-ground inclined plane, to give 

 notice when the empty boat is upon^ the waggon, or cradle, 

 and when the men below are ready, that the loaded boat may 

 be let down by the men above, k k, Holdfaft-ropes faftened 

 to the main-ropes, and hooked on to a ring at the fou-th end 

 of each boat, as it goes up or down, in order to ftay the 

 boats upon the waggon or cradle, that they may not fwag, 

 or (lip otf. Thcfe holdfaft-ropes are fpliced on to the end of 

 the main-ropes, and run above and between the two bridle- 

 ropes when they are fattened to the iron uprights, which are 

 upon each fide of the waggons, or cradles; andjheyruu 

 over the north end of the boat, to be hooked on to the fouth 

 end. //, the bridle-ropes faltened to the main-ropes at O, 

 and fecured to two iron uprights upon each fide of the wag- 

 gon, or cradle. O O, the places where the main-ropes, the 

 bridle-ropes, and the holdfaft-ropes, are fattened all together. 

 No. I. An open fpace driven into the fide of the lock A, to 

 which a pit is funk from the higher level, in order to convey 

 the water out of the locks down to the lower level, and alfo to 

 force a current of frefh air into the lower level collieries. 

 No. 2. A paddle to let the water out pf the lock A, into the 

 pit No. I. No 3, A paddle to let the water out of the 

 lock B, through a culvert, rtprefented by dotted lines, under 

 the lock A, into th-e pit No. i. No. 7,7. Paddles in the 

 lock-gates, to let the water out of the higher level into the 

 locks. No 8, 8. The two north lock-gates, one to each 

 lock, which turn upon the heqlsof the gates, and fwing round 

 when they are opened or iliut. No. 10, 10. Two ttops or 

 doughs, one to each lock, which ferve as lock-gates to the, 

 fouth end, and arc raifed and let down by a windlafs. S, a 

 iiop, which is ufed occafionally when the lock-gates want 

 rtpairing, T^ the place \yhere the boats which are to pafa 



to 



