BOOK VI. 



211 



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A — Machine first described. B — This workman, treading with his feet, is com- 

 pressing THE bellows. C — Bellows without nozzles. D — Hole by which heavy 



VAPOURS OR blasts ARE BLOWN OUT. E — CONDUITS. F — TUNNEL. G — SECOND 



machine described. H — Wooden wheel. I — Its steps. K — Bars. L — Hole in 

 SAME wheel. M — Pole. N — Third machine described. O — Upright axle. 

 P — Its toothed drum. Q — Horizontal axle. R — Its drum which is made of rundles. 



