!4 Of the Management of Fire 



them were distant from it near 15 feet, yet they were all 

 heated with great facility, and in a short space of time, 

 by the heat which, upon opening the valves (which 

 were of iron), was made to pass through the canals. 



Each boiler having its separate canal and its separate 

 valves, any single boiler, or any number of them, might 

 be heated at pleasure, without heating the rest ; and by 

 opening the valves of any boiler more or .less, more or 

 less heat, as the occasion required, might be made to 

 pass under the boiler; and when no more heat was 

 wanting for any of the boilers, or when the fire was too 

 strong, by opening a particular valve a communication 

 with a waste canal was formed, by which all the heat, or 

 any part of it at pleasure, might be made to pass off 

 directly into the chimney, without going near any of 

 the boilers. 



The fire was regulated by a register in the door of 

 the ash-pit, by which the air was admitted into the fire- 

 place ;' and, when no more heat was wanted, the fire was 

 put out by closing this register entirely, and by closing 

 at the same time all the valves or dampers in the canals 

 leading from the fire-place. 



The fire-place was of an oval form, 3 feet long, 2 feet 

 3 inches wide, and about 18 inches high, vaulted above 

 with a double vault, 4 inches of air being left between 

 the two vaults; and the fuel was introduced into the 

 fire-place by a passage closed by a double iron door, 

 which door was kept constantly shut; and the fuel 

 was burned upon an iron grate, the air which supplied 

 the fire coming up from below the grate through the 

 ash-pit. 



The loss of heat in its passage from the fire-place 

 to the boilers was prevented by making the canals of 



