OBSEUVATIONS ON HEATING A PIT. 



75 



three brackets, xxx, and be thrown down by a little rod with a liook, 

 or be fixed on two pivots, and secured by a catch, so as to turn over 

 and allow the clinkers to fall out when required. 



N?3 



No. 4. Exhibits the apparatus complete ; the lead pipe a from the 

 top of the boiler enters the lower side of the cast iron pipe A, while 

 from B. the other extremity of the range of iron pipes, the lead pipe b, 

 enters the top of this reservoir R. a strong cask answers the purpose per- 

 haps as well as any thing. From the lower side of this reservoir, a lead 

 pipe c, communicates with the union joint at the bottom of the boiler. 

 A supply cistern placed so that its bottom is higher than the highest 

 part of the iron pipe, and communicating with the bottom of the reser- 

 voir, and a valve not lower than the top of the supply cistern, with an 

 air pipe on the highest point of the iron pipes, complete the appa- 

 ratus. 



The fire being lighted in the furnace, the heated water flows into 

 the iron pipe and thence into the reservoir, till all be heated. When 



