568 Professor George Lunge [March 15, 



about solely by coal, without the aid of which it is simply impossible 

 to imagine the revolution which has taken place since then. 

 " Railways ! " That single word, to give only one instance, will 

 bring this home to anyone who ponders over this matter. And it is 

 equally impossible for us to imagine that, during the past century, 

 there could have been any other invention, based upon the utilisation 

 of the other supplies of energy of which we have spoken, which could 

 have replaced the untold services of coal, that accmmilator of solar 

 energy, which alone has enabled the human mind to work out the 

 thousand and one channels through which modern civilised life is 

 flowing. We may say this with all confidence, for how otherwise 

 could we account for the fact that such inventions have not been 

 made in former times, when there were certainly quite as many 

 ingenious minds in the world as during the coal-consuming age ? 



Let us now come down to considerations of a more modest, but 

 more practical nature than those in which we have just been indulg- 

 ing. Seeing that the stock of mineral fuel upon this earth is so very 

 limited, cannot we find means of husbanding it more than this has 

 been done hitherto ? It is only too notorious that the way in which 

 coal is at present consumed, is most wasteful. Of the energy residing 

 in coal, most ordinary steam-engines utilise less than 10 per 

 cent, by converting it into mechanical motion ; and even the most 

 perfect steam-engines devised utilise hardly more than 15 per cent. 

 Improvements in this direction may possibly sw^ell this proportion a 

 little, but there is no prospect of gaining much in that direction. 

 Enormous wastages are also incurred in other ways. The conversion 

 of pig-iron into steel, the manufacture of glass, and many other 

 industries consumes from four to twenty times, and even more, of the 

 quantity of coal required by theory. Many descriptions of coal are too 

 poor to be used at all except in the immediate vicinity of the spot where 

 they occur ; and in burning our fuel, whether it l)e for industrial or 

 for technical purposes, we invariably send its nitrogen into the atmo- 

 sphere, which surely contains quite enough of that commodity ; the 

 only exception being the manufacture of coal-gas, to which we shall 

 refer later on. Here some of the grandest problems of applied 

 chemistry present themselves to us — how to stop that fearful waste 

 of fuel ; and how to recover the nitrogen of the coal, if that be 

 possible. 



It is certain that we must look for the solution of these questions 

 in the direction of converting coal into gaseous fuel. It is true that 

 much has been done in that field in past years, and more especially 

 will the name "Siemens" occur to every one in this connexion, but 

 much more remains to l)e accoiny)lished. Another great stride ahead 

 lies in the ])etter utilisation of the waste gases from l)last furnaces, in 

 which respect the last few years have witnessed some very important 

 improvements. All tliis refers merely to a better utilisation of the 

 heating power of coal, Init not to that other great task, the recovery 



