Trippel.J ]^g [February. 



The cross section of the gas combustion canal is 5.3 square feet, 

 less the cross section of the tuyers, 0.395 square feet = 4.905 square 

 feet. The quantity of gas entering this canal is 80 cubic feet per 

 second, or 4800 cubic feet per minute. The velocity will be then at 



its entrance, V = Tqm, '^^ ^'^^ ^^^^ V^^ minute, and 16.3 feet per 

 second. 



As the smallest cross section of the gas-flues is = 3.85 square 



feet, we have the velocity in them, V = -^-^ = 1246 feet per 



minute, and 20.8 feet per second, with a corresponding head of 

 = 0.087 inches in a water column, or 6.74 feet in an air column. 

 The pressure in the air pipes, branching out from the main canal 

 and leading to the hot air apparatus, being necessarily the same 

 as that of the tuyers in the injector, = 1.5 inches in a water 

 column, we have to regulate the circular valves, so as to admit per 



10.-59 

 second 10.59 cubic feet of air under the same pressure = ^"- j, — 



0.0203 square feet for each generator = 3 square inches. 



The amount of consumed coal per hour is 952 lbs. for six genera- 

 tors, atid ] 58 lbs. for one, and per hour. 



The open spaces of the coal are estimated to be about 2.14 square 

 feet for each grate, and the velocity of produced gas in the gene- 

 rator = 2TAP, = 6 ^^ ^^^^ P®"" second. 



There were 18048 cubic feet products of combustion at a tempe- 

 rature of 4928° Fahrenheit, per minute. As they pass under the 

 boiler with a temperature of 2912° Fahrenheit, their volume is re- 

 duced to 7320 cubic feet (27.46. [4.46.60]); and when they leave 

 the boiler with an estimated temperature of 1301° Fahrenheit, it is 

 further reduced to 5832 cubic feet (27.46. [3.54.60]), by the di- 

 minished expansion. 



We would have then a velocity of -~ = 97 feet per second. 



The cross section of the entrance of the gas in the chimney is 

 1 square foot, and the corresponding head =: 1.86 inches in a water 

 column, or 144 feet in an air column. 



Comparing this head with that necessary for the passage of the gas 

 into the gas-flues, we find that we have an excess of =z 144 — 6.74 

 = 137 feet of an air column. This pressure is too much, for the hot 

 gas would escape through the working doors, to the injury of the 

 workmen. But in making the cross section 2 square feet, the velocity 



5832 

 would be -7^ =: 48.6 feet, and to corresponding head =: 35.2 feet 



