ON CONSUMPTION OP FUEL AND PREVENTION OF SMOKE. Ill 



It is well known that in practical operations there is no combustion without 

 oxygen as its supporter, and as that important element cannot be procured 

 for general purposes without the other constituents of atmospheric air, it 

 follows, that in order to effect combustion, a regular supply of this compound 

 must be constantly at command. Now it is not the facility, but the control 

 and regulation of the supply of air which requires attention, and on this point 

 of the inquiry we must refer to the researches of Mr.C.W. Williams, where, in 

 speaking of " gaseous combinations," he shows that much depends upon the 

 conditions and proportions in which the gases evolved during the process of 

 combustion combine with the oxygen of the air. And in order to effect this, 

 it is necessary for those entrusted with the management of furnaces to know 

 the " equivalents " or definite proportions under which these combinations 

 take place. On this head it will be sufficient to observe, that the principal 

 gases evolved from coal in a state of combustion are carburetted hydrogen, 

 bicarburetted hydrogen, and some others, such as carbonic acid gas, carbonic 

 oxide, &c., the properties of which it is not requisite on this occasion to in- 

 vestigate, but to confine the inquiry to the union of carburetted hydrogen, 

 bi- carburetted hydrogen, and atmospheric air. Following, therefore, the 

 Daltonian theory, it will be found that the constituents of one atom of car- 

 buretted hydrogen consist of the following symbols, each representing an 

 atom, and the figures the weight : — 



Carburetted hydrogen. 



I Hydrogen. | 

 \ // Carbon. \ 



Carburetted hydrogen is therefore composed of 2 hydrogen and 1 carbon 

 = 1 carburetted hydrogen. In weight 2 hydrogen + 6 carbon = 8 carbu- 

 retted hydrogen. The constituents of bi-carburetted hydrogen are 2 hy- 

 drogen and 2 carbon = 1 bi-carburetted hydrogen. In weight, 2 hydrogen 

 and 12 carbon, or 2 -|- 12 = 14 bi-carburetted hydrogen. 



These are the two principal gases which require attention, and as the 

 oxygen of the air is an element that cannot be dispensed with, the object of 

 our next inquiry will be into the quantity and constituents of atmospheric air. 



According to the best authorities atmospheric air is found in the propor- 

 tion of 1 oxygen and 2 nitrogen, or according to Mr. Williams (adopting the 

 figures as representing the weights as before), — 



Atmospheric Air.^ 



