APPLICATION OF WASTE STEAM. 



151 



glATBMEHT Ot EXPERIMENT WITH WaSTB StHAM, AS A MEDIUM OF BoiIOM HeAT, 

 MADE AT PbNLLEKOABE, 1850. 



From this it appears, 1st, that although steam was introduced among 

 the stones for only twenty minutes a day, the temperature was raised 

 from 51° to 68° in the first twenty-four hours ; 2nd, that the tempera- 

 ture continued to rise for many hours after the second application of 

 steam, until the thermometer reached 108° ; 3rd, that at the end of 

 nineteen hours the heat of the 'frame diminished; yet 4th, that at the 

 end of seventy hours the temperature still was 69°, This appears a 

 conclusive answer to those who think that masses of heated water, or 

 heated porous materials, like, rough stones, will become so reduced in 

 temperature by a few hours' withdrawal of the prime heating power as 

 to endanger the plants cultivated in houses thus warmed. The experi- 

 ment continued to be successful, and enabled Pine-apples of the most 

 perfect quality to ripen. 



