xl KANT'S UNIVERSAL NATURAL HISTORY 



solution, which probably came to him in a quick 

 flash of thought, as has been so often the case 

 with men of genius when they suddenly grasped 

 a new discovery. Kant may have even intended 

 to submit an essay in competition, and it is some- 

 times stated that he did this ; but assuredly he 

 did not do it. Although his solution was most 

 clear and certain to his own mind, he could not 

 work it out with the fulness of demonstration which 

 he considered was necessary to satisfy the con- 

 ditions of the problem. He could find no historical 

 evidence of any alteration in the period of the 

 daily rotation of the earth ; but he recognised, 

 apparently for the first time, a physical cause con- 

 stantly in action, which must bring about a certain 

 retardation of the earth's rotation round its axis. 

 This cause he discerned in the action of the Tides 

 as, moving from east to west, they constantly 

 break upon the surface of the earth in its opposing 

 and resisting movement from west to east. This 

 was Kant's original discovery of the effect of tidal 

 faction in retarding the earth's rotation. He did 

 not send in a competitive essay, but he published 

 his solution, so far as worked out, in a weekly 

 Konigsberg journal, entitled the WocJientliche Frag- 

 und A nzeigungs-Nachrichten (a sort of ' Weekly 

 Notes and Queries'), in which scientific contribu- 

 tions of the kind occasionally appeared. Kant's 

 paper appeared in Nos. 23 and 24, i.e., about the 

 middle of June, 1754. 



