298 THE POPULAR SCIENCE MONTHLY. 



be closed by a close-fitting stopper or door. In fireplaces constructed 

 for small stew-pans this opening may be omitted, and the fuel be 

 introduced through the opening into which the stew-pan is fitted, by 

 removing the stew-pan occasionally for the purpose. 



4. All portable stew-pans should be circular, and suspended in their 

 fireplace from the circular rim. The best form for large fixed boilers 

 is an oblong square, broad and shallow rather than narrow, and deep, 

 and it should be of thin metal. 



5. All boilers and stew-pans should be fitted with covers to render 

 them well adapted for confining the heat. The best arrangement is to 

 make the covers of thin sheets of tinned iron, and double, that is, with 

 an air space between the outer and inner cover. 



We have, during the last twenty years, introduced, as a rule, close 

 ranges. They are certainly cleaner and more convenient for cooking, 

 and, if great care is exercised in the use of the dampers, they will be 

 found more economical than open fires. But, as a rule, they are based 

 on the principle of making one fire perform a variety of operations. 

 Independently of the question of a combined fire, as compared with 

 the separate fires advocated by Count Rumford, a consideration of the 

 form of modern kitchen-ranges will show that most of the principles 

 laid down by him have been entirely neglected. The doors of the 

 fireplace and ash-pit seldom fit close ; the boilers are rather deep and 

 narrow than broad and shallow ; the use of the hot-plate prevents the 

 stew-pans from being suspended from the rims for the fire to play 

 round them; the use of double covers for saucepans and boilers is 

 rather a rarity than a usual arrangement. 



To realize the question of economy of fuel, it is necessary to con- 

 sider, in the first place, what a given quantity of fuel is capable of 

 doing. As regards hot water, if water is kept at a temperature of 

 200, or from that to 210, the gases from the fire can, after communi- 

 cating the heat to the boiler, pass off into the chimney at a tempera- 

 ture of little beyond that point ; but, if the water be allowed to boil, 

 in the first place a large amount of latent heat is absorbed by the 

 steam, which is lost if the steam passes off into the air or the chimney, 

 and, in the second place, it will be found that the gases, after they 

 pass off from the boiler, will have a temperature of as much as 300, 

 400, and even 500. Unless, therefore, water is required to be actu- 

 ally boiling for use, if the water is permitted to boil, a great quantity 

 of heat is wasted up the chimney. For household purposes it is never 

 necessary that the water in the boiler should exceed 200. Tea, to be 

 good, should be made (as clearly shown by Mr. Francis Galton in his 

 "Art of Travel") with water of a temperature of from 180 to 200. 

 Very few culinary operations require the water really to boil, and, 

 when boiling water is wanted, it is required in a saucepan standing on 

 the fire. All operations of cleaning, etc. (except washing clothes), 

 require water at a very much lower temperature than 212. If, however, 



