1 6 Of the Management of Fire 



the cone being closed by a circular plate or thin sheet 

 of tinned iron. The bottom of the cone was accu- 

 rately fitted to the top of the boiler, which it completely 

 closed, by means of a rim about 2 inches wide, which 

 entered the boiler; which rim was soldered to the flat 

 sheet of tinned iron which formed the bottom of the 

 cover. The steam generated by the boiling liquid 

 was carried off by a tube about half an inch in diarn- 

 eter, which passed through the hollow conical cover, 

 and which was attached to the cover, both above and 

 below, with solder, in such a manner that the air with 

 which the hollow cone was filled remained completely 

 confined, and cut off from all communications with the 

 external air of the atmosphere, as well as with the 

 steam generated in the boiler. 



In some of the covers I filled the hollow of the cone 

 with fur, but I did not find that these were sensibly 

 better for confining the heat than those in which the 

 cone was filled simply with air. 



To convince the numerous strangers, who from curi- 

 osity visited this kitchen, of the great advantage of 

 making use of double covers to confine the heat in the 

 boilers, instead of using single covers for that purpose, 

 a single cover was provided, which, as it was externally 

 of the same form as the others, when it was placed 

 upon a boiler, could not be distinguished from them ; 

 but as its bottom was wanting, and consequently there 

 was no confined air interposed between the hot steam 

 in the boiler and the external surface of the cover, on 

 being placed upon a kettle actually boiling, this cover 

 instantaneously became so exceedingly hot as actually 

 to burn those who ventured to touch it ; while a double 

 cover, formed of the same materials, and placed in the 



