Steam:
Its Generation and Use

•>£ its equivalent of oxygen, and must find it while hot enough to combine, in order to be effective. In this boiler the currents of gases after leaving the furnace are broken up and thoroughly mingled by passing between the staggered tubes, and have an opportunity to complete their combustion in the triangular chamber between the tubes and drum. That this does really take place is proved by an analysis by Dr. Behr of the escaping gases from a stack of these boilers at Mattheissen & Weicher’s sugar refinery. He made many sepa- rate analyses at different times, and in no case was there more than a trace of carbonic oxide, tact with all parts of the heating surface, render- ing it much more efficient than the same area in ordinary tubular boilers. The experiments of Doctor Alban and of the U. S. Navy have proved that a given surface arranged in that manner is thirty per cent, more efficacious than when in the form of fire tubes as usually employed. fl.—Efficient Circulation of Water. As all the water in the boiler tends to circulate in one direction, there are no interfering currents, the steam is carried quickly to the surface, all Babcock & Wilcox Boilers, 120 H. P.( at the Vancorlear Apartment House, New York. Erected 1878. Showing style of Ornamental Cast Iron Front. even when there was less than one per cent, of uncombined oxygen. 5.—Thorough Absorption of the Heat. There are important advantages gained in this respect in consequence of the course of the gases being more nearly at right angles to the heating surface, impinging thereon instead of gliding by in parallel lines as in fire-tube boilers. The cur- rents passing three times across and between the staggered tubes are brought intimately in con- parts of the boiler are kept at a nearly equal tem- perature, preventing unequal strains, and by the rapid sweeping current the tendency to deposit sediment oti the heating surface is materially lessened. 7.—Quick Steaming. The water being divided in many small streams, in thin envelopes, passing through the hottest part of the furnace, steam may be rapidly raised in starting, and sudden demands upon the boiler may be met by a quickly increased efficiency. 38