122 Book of Engineering 



to be in good condition, ready to take the 

 place of the old one. 



The glass-house is never a cool place 

 with the furnaces constantly at white heat, 

 but the actual breaking down of a side of 

 the casing which holds the old pot makes 

 the place an inferno. Clothes, as far as 

 possible, are discarded. Working quickly 

 the old pot is brought out by the use of 

 the strange tools, each having its own par- 

 ticular task. For some reason the men shout 

 a medley of instructions, some of which 

 must be disregarded, since one man is 

 obviously contradicting the order given by 

 his mate. 



The old pot out, the new one must be 

 put in its place without delay, and certainly 

 without being allowed to cool down, or 

 danger would result, and almost certainly 

 it would crack badly. 



With a deftness born of long practice the 

 new pot, weighing at least half a ton, is 

 slid into position, and the aperture through 

 which it was inserted is made good by 

 firebricks, and also wet clay for finish- 



