54 



Professor W. A. Bone 



[Feb. 27, 



3 feet in length and 3 inches in diameter, packed with fragments of 

 granular refractory material, meshed to a proper size, and fitted at 

 one end with a fire-clay plug, through which was bored a circular 

 hole, f inch in diameter, for the admission of the explosive mixture 

 of gas and air at a speed greater than that of back firing (Fig. 9). 

 The tube was fitted into an open trough, such as you see here on the 

 table, in which water could be evaporated at atmospheric pressure. 

 After the lecture my assistants will demonstrate the boiling of water 

 in this apparatus. 



'. ! 5 Such a tube may be appropriately termed the fundamental unit 

 of Jour boiler system, because boilers of almost any size may be con- 



DI/IGRflM or THE FUND/lMEIiT/IL BOILER UNIT 



1500 



100 CUB n CORL 

 G0S PLUS 55 

 CUB nm 



HOUR 



TOTflL HifiJ TRUtiSniTTCD - 67i^ OT NUT CflL V/HUC OF GHS . 

 TOTAL tWMPOUffTION ' 100 LBS WffTElR PER HOUR FROM UNO 



AT I00'C(ZI2°F). 

 MZflli HVflPORflVON PER SO FT HEATING SURFACE - ZO-ZZ 



LBS PER HOUR FROM HND AT IOC' C(glZT). 



ZOO' 



PRODUCT 3 LCffVING 

 AT ZOO'C 



70 ' ZZ ' 8 



* or TOTHL €V/IPOR»TION FOR EHCH LINEAR FOOT 



Fig. 9. — Diagram of the Fundamental Unit. 



structed merely by multiplying the single tube, and as each tube is, 

 so to speak, an independent fire or unit, the efficiency of the whole 

 is that of the single tube, or in other words, the efficiency of the 

 whole boiler is independent of the number of tubes fired. 



Experimenting with such a tube, it was found possible to burn 

 completely a mixture of 100 cubic feet of coal gas plus 550 cubic feet 

 of air per hour, and to evaporate about 100 lb. of water from and at 

 100° C. (212° F.) per hour (20 to 22 lb. per square foot of heating 

 surface), the products leaving the further end of the tube at prac- 

 tically 200° C. This meant the transmission to the water of 88 per 

 cent, of the net heat developed by the combustion, and an evapora- 



I 



