ON THE PHYSICAL VIEW OP NATUHE. I.'i5 



new substance witli sUiiLling properties — be tliey useful 

 or only curious and rare — has almost innuediately a 

 value, whereas the manifold transformations by which 

 it was discovered, invented, or produced escape general 

 notice, and are accordingly of secondary interest. This 

 interest grows in proportion as another factor of ec^ual 

 commercial importance gradually and slowly asserts 

 itself, namely, the factor of cost of ])roducti(jn, the 3«. 

 property through which not only the material itself, "e.«if in 

 but also the labour bestowed upon it, and the most 

 intricate transmutations and secret manipulations, gain 

 a place and definite figure in the ledger of the 

 accountant. Those of us who entered into practical 

 life about the beginning of the last generation of the 

 century know well by experience how then for the first 

 time was being established the great system of statistics, 

 of cost of production, which now governs every well- 

 conducted industry and manufactory, though in general 

 this department is still but little understood. Now, in 

 proportion as with progressing civilisation we come more 

 and more to use artificially prepared products in the 

 place of natural ones, the cost-figures become more com- 

 plex : there is not only the raw material and the labour 

 of getting it, not only the general economy of arrange- 

 ment and administration by which we save labour and 

 avoid waste — there is the whole aggregate of changes 

 and processes, manual, mechanical, and chemical, through . 

 which the raw material has to pass. These must all 

 have a common measure 1)y which they possess a iigure 

 of value in the ledger of the book-keeper, otherwise the 

 latter r-nuld not ]>ro(luce a statement of cost. Watt, 



