INDEX. 251 



Plant of six 60-inch horizontal return tubular boilers with double passage 

 for products of combustion, 75. 



Plant of two 54-inch horizontal return tubular boilers with flue heater, 140. 



Plant of two 60-inch horizontal return tubular boilers with flue heater, 142. 



Plant of four plain cylinder boilers, 174. 



Plant of live vertical tubular boilers, 196. 



Plant of two vertical tubular fire box boilers with large heating sur- 

 face, 208. 



Plant of two vertical tubular fire-box boilers, without superheating, 203. 



Plant of two vertical tubular nest boilers, 199. 



Plant of two vertical tubular rolling-pin boilers with flue heater, 205. 



Plant of two water-tube boilers, 231. 



Plant of two water-tube boilers with flue heater, 224. 



Plant of four water-tube boilers with coil of pipe in flue, 219. 



Power, Relative, with different fuels, 48, 80, 91, 102. 



Prevention of smoke, 53, 62, 113, 122, 137, 159. 



Prevention of smoke by admitting air above fuel, 53, 62, 113, 137, 159. 



Proportion of heating surf ace to grate surf ace, Effect of, upon economy, 32. 



Proportion of heating surface for best results, 32. 



Proportion of tube opening to grate surface, Effect of, upon economy, 34. 



Proportions of air space in grates, Tests with different, 60, 95. 



Quality of steam, Method of determining, 17. 

 Quality of steam, Calorimeter t?sts of the, 62. 



Rapid combustion, Economy of, 183, 187, 198. 



Rate of combustion, Effect of changing, 103, 106, 108, 168, 176, 189, 198, 



202. 



Relative amount of power developed with different fuels, 48, 80, 91, 102. 

 Relative economy of different kinds of boilers, 36, 

 Relative economy of different kinds of fuel, 43, 80, 101, 109, 115, 118, 150, 



163, 166, 194, 197. 

 Relative labor of firing different coals, 80, 119, 196. 



Screenings burned with forced draught, Tests with, 86, 190. 



Sectional boilers. Cast iron, 211, 213, 215. 



Shape of bridge wall, Effect of, upon economy, 51. 



Size of shell, Effect of, upon economy, 34. 



Size of tubes, Efl'ect of, 35, 134. 



Smokeless furnace, 136. 



Steam heating surface at top of shell, Effect of, 67, 93. 



Stove coal, Tests with, 115. 



Summary of Tests, 234. 



Summary of Tests with flue heaters, 57. 



Superheated steam, Boilers producing, 67, 154, 183, 187, 190, 192, 196, 199, 



201, 205, 209, 211, 215. 



Superheater with horizontal boiler and auxiliary furnace, 67. 

 Superheating, Allowance for, 22, 186. 



