3(54 



HEATING APPARATUS. 



212 degrees. One bushel of coal will raise the temperature of 

 3600 Ibs. of water from 40 to 212 degrees. 



"A boiler, as the drawing, will contain 1200 Ibs. of water, 

 and consume one-third of a bushel of coal to raise the water 

 from 40 to 212 degrees. It has 40 surface feet of hot sides 

 giving out its heat. The 12-inch fire-tube in the boiler would 

 raise the temperature to 212 degrees in about forty minutes. 

 By these proofs it appears that 50 feet of surface steam sides 

 will require 1 bushel of coal every twenty-four hours to keep 

 up the boiling heat; therefore this boiler, having 40 surface 

 feet, would give out the heat from one-third of a bushel of coal 

 in twelve hours. 



" Now suppose this charge of heat required to be thrown off 

 in either more or less than twelve hours, the circular curtain 

 would adjust the heat and time for extracting it. 



" By the foregoing this coal and surface sides would heat to 

 60 degrees for twelve hours a space of 6800 cubic feet, equal 

 to a room of 25 feet square and 11 feet high. If this boiler 

 was placed in a room with a chimney, its water could be 

 heated by having a small shifting wrought-iron chimney-tube 

 of 4 inches diameter and 2 or 3 feet long attached to the end 

 of the boiler while it was getting up steam, after which it might 

 be removed, and the doors at both ends of the boiler closed ; 

 and as the boiler contains and retains its heat for twelve hours, 

 more or less, it might be run on its wheels to any fire-place or 



HOT-WATEB ROOM-WARMER. 



chimney to get charged with heat, and then run into any room, 

 where there was no chimney, or into bed-rooms, offices, or 

 public buildings ; it would be free from risk, not having either 

 steam or loose fire. The circular curtain, being fast to a wood 



