205, 206] Dissipation of Energy 175 



that if the passage C is sufficiently narrow this last amount may be very 

 small, and hence that the temperature of the gas in A will remain perceptibly 

 constant for a great time. It will be seen, then, reverting to the real gas, 

 that the temperature of this gas can remain perceptibly constant for a great 

 time if the analogy is a true one, and if the transfer of energy which has 

 been represented by the transfer of heat through the passage can be shewn 

 to be sufficiently slow. To examine this transfer will be the problem of 

 Chapter IX. Meanwhile it is hoped that the analogy suggested in the 

 present section, although of course not representing a step in the main 

 argument, will be of service in making clearer the direction in which this 

 main argument is tending. 



