SCIENCE IN RELATION TO THE ARTS. 55 



tee. charged with the final determination of the Obm, one of its most 

 distinguished members, Lord Rayleigh, has, with his collaborateure, 

 Mrs. Sidgwick, continued his important investigation in this direction 

 at the Cavendish Laboratory, and has lately placed before the Royal 

 Society a result which will probably not be surpassed in accuracy. 

 His redetermination brings him into close accord with Dr. Werner 

 Siemens, their two values of the mercury unit being 0-95418 and 

 0*9536 of the B. A. unit respectively, or 1 mercury unit = 0-9413 X 10 9 

 C. G. S. units. 



Shortly after the publication of Lord Rayleigh's recent results, 

 Messrs. Glazebrook, Dodds, and Sargant, of Cambridge, communicated 

 to the Royal Society two determinations of the Ohm, by different 

 methods ; and it is satisfactory to find that their final values differ 

 only in the fourth decimal, the figures being, according to 



^ . , ~, ~~ Earth Quadrant 

 Lord Rayleigh 1 Ohm = 0-98651 a . 



J Second 



Messrs. Glazebrook, etc. = 0-986439 







Professor E. Wiedemann, of Leipsic, has lately called attention to 

 the importance of having the Ohm determined in the most accm-ate 

 manner possible, and enumerates four distinct methods, all of which 

 should unquestionably be tried with a view of obtaining concordant 

 results, because upon its accuracy will depend the whole future system 

 of measurement of energy of whatever form. 



The word " energy " was first used by Young in a scientific sense, 

 and represents a conception of recent date, being the outcome of the 

 labors of Carnot, Mayer, Joule, Grove, Clausius, Clerk - Maxwell, 

 Thomson, Stokes, Helmholtz, Macquorn-Rankine, and other laborers, 

 who have accomplished for the science regarding the forces in nature 

 what we owe to Lavoisier, Dalton, Berzelius, Liebig, and others, as 

 regards chemistry. In this short word " energy " we find all the efforts 

 in nature, including electricity, heat, light, chemical action, and dy- 

 namics, equally represented, forming, to use Dr. TyndalPs apt expres- 

 sion, so many "modes of motion." It will readily be conceived that, 

 when we have established a fixed numerical relation between these 

 different modes of motion, we know beforehand what is the utmost 

 result we can possibly attain in converting one form of energy into 

 another, and to what extent our apparatus for effecting the conversion 

 falls short of realizing it. The difference between ultimate theoretical 

 effect and that actually obtained is commonly called loss, but, consid- 

 ering that energy is indestructible, represents really secondary effect 

 which we obtain without desiring it. Thus friction in the working 

 parts of a machine represents a loss of mechanical effect, but is a gain 

 of heat, and in like manner the loss sustained in transferring electrical 

 energy from one point to another is accounted for by heat generated 



