Twentieth century hand-book for steam engineers and electricians with questions and answers; a practical non-technical treatise .. (1913)
Swingle, Calvin Franklin, 1846- [from old catalog] · Chicago, F. J. Drake & company · leaf 138
hes and soot canthen be easily cleaned out by means of a long-handled hoeor scraper inserted through tbe cleaning out door, whichshould always be placed in the back wall of every boiler set-ting. Back Arches, A good and durable arch can be madefor the back connection, extending from the back wall… … Fig. 49
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