Fire-places and Kitchen Utensils. 375 



torn of the upper boiler. This projection prevents the 

 water resulting from the condensation of steam against 

 the sides of the upper boiler from descending into the 

 lower boiler. The upper boiler is 8| inches deep, from 

 the top of the inside of its steam-rim to the flat part 

 of its bottom. The whole depth of both boilers is 18 

 inches, from the top of the steam-rim to the lower 

 boiler. 



A circular piece of tin, about 22 inches in diameter, 

 with many holes through it to give a free passage to 

 the steam, being laid down in a horizontal position 

 upon the top or projecting brim of the lower boiler, 

 upon this circular plate the shallow dishes are placed, 

 which contain the victuals that are to be cooked in 

 steam. Two such dishes are faintly represented in the 

 foregoing figure by dotted lines. 



The cover of this universal boiler is a shallow circu- 

 lar dish, 26 inches in diameter at its brim, and about 

 1 2 inches deep, turned upside down, and covered above 

 with a circular covering of wood to confine the heat. 

 The handle to this cover is a strong cleat of wood, fas- 

 tened to the circular wooden cover by means of four 

 wood screws. This handle is distinctly represented in 

 the figure. 



The circular wooden cover for confining the heat 

 must be constructed in panels, and must be fastened 

 to the shallow metallic dish by means of rivets or wood 

 screws. In doing this, all the precautions must be taken 

 that are pointed out in the fifth chapter of this Essay, 

 page 289; otherwise the wood and the metal will be 

 separated from each other, in consequence of the 

 shrinking of the wood on its being exposed to heat. 



The inverted shallow dish, which, properly speaking, 



