2 LINKS WITH THE PAST [CH. 



whose ancestors flourished during periods of the 

 earth's history long ages before the advent of the 

 human race. 



In dealing with plants of former ages we are 

 confronted with the difficulty of forming an adequate 

 conception of the length of time embraced by geo- 

 logical periods in comparison with the duration of 

 the historic era. Some of the ' Selections from the 

 Greek Papyri' recently edited by Dr Milligan 

 (Cambridge 1910) refer to common-place events in 

 terms familiar to us in modern letters : we forget 

 the interval of 2000 years which has elapsed since 

 they were written. Similarly, the close agreement 

 between existing plants and species which lived in 

 remote epochs speaks of continuity through the ages, 

 and bridges across an extent of time too great to 

 be expressed by ordinary standards of measurement. 

 Terms of years when extended beyond the limits 

 to which our minds are accustomed cease to have 

 any definite meaning. While there is a certain 

 academic interest in discussions as to the age 

 of the earth as expressed in years, we are utterly 

 unable to realise the significance of the chronology 

 employed. After speaking of the futility of attempting 

 to introduce chronological precision into periods so 

 recent as those which come into the purview of 

 archaeologists, Mr Rice Holmes suggests a method 

 better adapted to our powers. He says — * Ascend 



