PREFACE IX 



we were, recantation would not affect the 

 question of evolution. 



I am glad to see that Lord Kelvin has just 

 reprinted his reply to my plea, 1 and I refer the 

 reader to it. I shall not presume to question any- 

 thing, that on such ripe consideration, Lord Kelvin 

 has to say upon the physical problems involved. 

 But I may remark that no one can have asserted 

 more strongly than I have done, the necessity 

 of looking to physics and mathematics, for help 

 in regard to the earliest history of the globe. 

 (See pp. 108 and 109 of this volume.) 



And I take the opportunity of repeating the 

 opinion, that, whether what we call geological 

 time has the lower limit assigned to it by Lord 

 Kelvin, or the higher assumed by other philoso- 

 phers; whether the germs of all living things 

 have originated in the globe itself, or whether 

 they have been imported on, or in, meteorites 

 from without, the problem of the origin of those 

 successive Faunae and Florae of the earth, the 

 existence of which is fully demonstrated by 

 paleontology remains exactly where it was. 



For I think it will be admitted, that the germs 

 brought to us by meteorites, if any, were not 'ova 

 of elephants, nor of crocodiles ; not cocoa-nuts nor 

 acorns ; not even eggs of shell-fish and corals ; 

 but only those of the lowest forms of animal and 

 vegetable life. Therefore, since it is proved that, 

 1 Popular Lectures and Addresses. II. Macmillan and Go. 1894. 



