218 SCIENCE IN SHORT CHAPTERS. 



perhaps, not so much ventilated) than a corresponding class 

 of house in England, where the outside temperature is 20 

 or 30 degrees higher, and this with a consumption of about 

 one-fourth of the fuel which is required for the production 

 of British bronchitis. 



This is done by, first of all, sacrificing the idiotic recrea- 

 tion of fire-gazing, then by admitting no air into the chim- 

 ney but that which is used for the combustion of the fuel; 

 thirdly, by sending as little as possible of the heat up the 

 chimney; fourthly, by storing the heat obtained from the 

 fuel in a suitable reservoir, and then allowing it gradually 

 and steadily to radiate into the apartment from a large but 

 not overheated surface. 



TheKussian stove by which these conditions are fulfilled 

 is usually an ornamental, often a highly artistic, handsome 

 article of furniture, made of fire-resisting porcelain, glazed 

 and otherwise decorated outside. Internally it is divided 

 by thick fire-clay walls into several upright chambers or 

 flues, usually six. Some dry firewood is lighted in a suit- 

 able fireplace, and is supplied with only sufficient air to ef- 

 fect combustion, all of which enters below and passes fairly 

 through the fuel. The products of combustion being thus 

 undiluted with unnecessary cold air, are very highly heated, 

 and in this state pass up compartment or flue No. 1; they 

 are then deflected, and pass down No. 2; then up No. 3, 

 then down No. 4, then up No. 5, then down No. 6. At the 

 end of this long journey they have given up most of their 

 heat to the 24 heat-absorbing surfaces of the fire-clay walls 

 of the six flues. 



When the interior of the stove is thus sufficiently heated, 

 the fire-door and the communication with the chimney are 

 closed, and the fire is at once extinguished, having now 

 done its day's work ; the interior of the stove has bottled 

 up its calorific force, and holds its ready fore mission into the 

 apartment. This is effected by the natural properties of 

 the walls of the earthenware reservoir. They are bad con- 

 ductors and good radiators. The heat slowly passes through 

 to the outside of the stove, is radiated into the apartment 

 from a large and moderately-heated surface, which affords 

 a genial and well-diffused temperature throughout. 



