356 THE APPLICATIONS OF PHYSICAL FORCES. [BOOK iv. 



very different for the three kinds of fuel, and we shall not be wrong in 

 stating that sixty per cent, at least is lost in smoke without being 

 utilized in any way. We have here then an annual loss of forty 

 millions of francs which might certainly be considerably reduced if 

 rationally constructed apparatus were everywhere adopted. The purse 

 and the health of consumers would be thereby equally benefited. 



What would be the result if we were to apply the same calculation 

 to the whole of France, and to all the countries of the world ? 



