Fig. 13. Huntingdon Mill.
A No. 4 Dodge stone-breaker working about 8 hours will keep a five foot Huntingdon Mill going 24 hours, and an automatic feeder is necessary. For that matter both are almost essential for an ordinary stamper battery, and will certainly increase the crushing capacity and do better work from the greater regularity of the feed.
A 10 h.-p. (nominal) engine of good type is sufficient for Huntingdon mill, rock breaker, self-feeder and steam pump. A five foot mill under favourable circumstances will crush about as much as eight head of medium weight stamps.
Fig. 14. Stone-Breaker.
