L. E. KNOTT APPARATUS CO., BOSTON 300 WORKING STEAM ENGINE MODELS … No. 69-76 69-75 WORKING STEAM ENGINE, of small size, for use with Steam Boiler No. 60-365 and consequently designed to work on exceedingly low pressure, operating smoothly without load, when the mercury manometer tube, the most convenient method of determining the exact working pressure, shows only…
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