BOOK VI. 



165 



A— Upright beams. B— Sills laid fl.\t upon the ground. C— Posts. D— Area. 



E-SiLL SET AT THE BOTTOM OF THE HOLE. F— AXLE. G-DOUBLE CROSS-BEAMS. 



H-Drum. I-Winding-ropes. K-Bucket. L-Small pieces of wood hanging 



FROM DOUBLE CROSS-BEAMS. M— ShORT WOODEN BLOCK. N— ChAIN. "— ^«^E BAR. 



P— Grappling hook. (Some members mentioned in the text are not shown). 



