( 100 )



CHAP. XVII.



DESCRIPTION OF PLATE XII. REPRESENTING THE SECOND MODE

OF PASSING THE ALTERNATE TRADE BY A PERPENDICULAR LIFE





	In constructing this machine, the tunnel and two pits are similar to the first life, and the drum-wheel of the two diameters, which must be so places, that one side may be over the center of the pit; the cage chains being fixed to the large, and the tub to the small diameter.



	One gate must then be placed on the end of the upper canal, as in the last machine; also one lock-carriage, moving parallel to the canal.



	On the side of the machine, and below the hind end of the lock-carriage, a small pond is formed to receive the water discharged from the lock carriage; which water is afterwards drawn into the tub, to create the preponderating power, and answer the double purpose of floating the boat into the cage, and then raising on from the bottom to the top canal.

	

	To regulate the movement of this machine, the centrifugal fans are applied, as before described.



	The expense of one hundred feet rise, about 2,500 l and the execution near three hundred and sixty tons in twelve hours.



	If these machines, the quantity estimated being the work of twelve hours, it consequently may be doubled by working at night; which, I hope, exhibits that lateral cuts might have been extended to great advantage by these machines.