736 REPORT— 1902. 



2 The Smokeless Combusfion of Bituminous Fuel. 

 By W. H. Booth, M.Am.Soc.C.E. 



The author points out that although engineeis are taught the conditions neces- 

 sary to combustion, they do not put them into practice, and the modern boiler is 

 tixed in the most primitive manner. 



Certain fuels burn without smoke, and may be burned directly below heat- 

 absorbing surface. This cannot be done smokelessly with hydrocarbons, because 

 of the greater avidity of hydrogen than of carbon for oxygen, and the necessity 

 of preserving a high temperature for burning hydrocarbon gas. 



The difference between long and short flaming coal is pointed out and the 

 effects noted. 



The effect of refractory furnaces is discussed. The refrigerating effect of 

 volatilising solid hydrocarbons is discussed in its effect on the distribution of 

 temperature in a furnace, and the production of heat at and beyond the grate 

 surface. Though less heat is produced at the grate surface, the total heat-pro- 

 duction of bituminous coal is eventually secured if suitable furnace arrangements 

 are provided for the purpose. 



The faults of everyday boiler-settings are pointed out in respect of various 

 types of boilers, and the bad effect of cold-water pipes in the path of the furnace 

 gases is referred to. Though very bad as a smoke producer, the common form of 

 water-tube boiler can easily be set so as not to produce smoke. The furnaces 

 must be so arranged that all the gaseous products of the furnace are swept 

 together with all the admitted air, and are not cooled down until sufficiently 

 burned to admit of being used. For this purpose furnace linings must be non- 

 heat absorbent. 



Small-tube boilers are condemned in their more common forms, and the 

 arrangement of the refractory furnace of the Weir boiler pointed out as affording 

 economical and smokeless combustion. 



The locomotive is also instanced as an example of how partial recognition of 

 the correct principles has been fairly successful. 



Some of the attempts to secure smokeless combustion are discussed, and the 

 conviction expressed that there is nothing in smoke prevention to justify the 

 assertion so often made that it is economically impossible. 



The final conclusion is that smokeless combustion of bituminous coal is as 

 easy and certain as the reverse method. 



3. The Prevention of Smoke. By 3. S. Raywobtii. 



4. The Solignac Boiler. By W. H. Booth. 



5. The Making of a Dynamo. By H. A. Mayor. 



6. Experiences with the Infantry Range-finder in the South African War. 

 By Professor G. Forbes, F.R.S. 



7. A Preliminary Note on Gas-engine Explosions.^ By H. E. Wimperis. 



In this note the writer refers to a previous paper published in the columns of 

 Engineering (June 27 and August 1,1902) in which the thermodynamic properties 

 ■of gaseous mixtures during explosion were investigated in the light of the results 



' Published in exienso in Engineering, October 10, 1902, and in the Eiigineer, 

 October 10, 1902. 



