252 Utilisation of the Power involved 



from physiologists ; but his total merit has never yet been recog- 

 nised as it assuredly would have been had he chosen a happier 

 mode of publication. I do not think a greater disservice could 

 be done to a man of science, than to overstate his claims ; such 

 overstatement is sure to recoil to the disadvantage of him in 

 whose interest it is made. But when Mayer's opportunities,, 

 achievements, and fate are taken into account, I do not think 

 that I shall be deeply blamed for attempting to place him in that 

 honourable position which I believe to be his due. 



Here, however, are the titles of Mayer's papers, the perusal of 

 which will correct any error of judgment into which I may have 

 fallen regarding their author. " Bemerkungen iiber die Krafte 

 der umbelebten Natur," Liebig's Annalen, 1842, vol. 42, p. 231 ; 

 '^ Die Organische Bewegung in ihrem Zusammenhange mit dem 

 Stoffwechsel ;" Heilbronn, 1845; "Beitrage zur Dynamik des 

 Himmels," Heilbronn, 1848; "Bemerkungen nber das Mechan- 

 ische Equivalent der W^rme," Heilbronn, 1851. 



ARTICLE XXIII. — On the Utilisation of the Power involved in 

 the Pise and Pall of the tides.* 

 The tendency of modern scientific discovery has been to show 

 that all the various forms of force with which we are acquainted 

 are mutually convertible into one another. Thus, of the six forces 

 known to us in connection with the universe — gravitation, motion, 

 light, heat, electricity, and chemical afiinity— it is well known 

 that any one of the five latter is capable, by appropriate means, 

 of generating the other four, the force of gravitation being ca- 

 pable, through the medium of motion, of giving rise to the other 

 five forces, whilst it cannot itself be generated. Gravitation may 

 therefore be assumed to be the elemental force, since it is the only 

 one of the six which will generate all the others. So accurately 

 have these correlations been studied, that the quantitative value 

 of gravitation has even been ascertained, it having been found 

 that the mechanical force required to lift 772 pounds to the height 

 of one foot, is capable, when converted into the force of heat, of 

 raising the temperature of one pound of water 1°F. In other 

 words, this amount of heat may be generated by an appropriate 

 utilisation of the gravitating pull, exerted by a weight of 772 

 pounds during its downward movement through the space of one 



*From the " Chemical News," 12th July, 1862. 



