THE EELATIONS OF GEOLOGY. 367 



The wanderings of early man from place to place and land to land 

 soon familiarized him with the idea of the extension of space. He had 

 learned by l)itter experience, times out of numher, that the distant 

 horizon which to the eye bounded the ^ast canopy of the sky aliovc 

 him was no l)oundary at all, l)ut shaded away in all directions into a 

 limitless Avorld beyond, whose practical infinity had been proved to 

 him by his own wanderings, and ])y those of his forefathers generation 

 after generation. Thus the idea of the vastness of space had already 

 become a part of man's intellectual equipment long before the origin 

 of astronomy itself. And this idea has been deepened, broadened, 

 and strengthened during the successive centuries of progress by the 

 emplo^nnent of constantly improving instruments of accurate meas- 

 urement, b}^ the invention of the telescope, the discoveries of geogra- 

 phy, and by the application of the higher mathematics to astronomy 

 as a whole. 



But early man (and, indeed, his successors even down to and beyond 

 the Middle Ages) Avas miserably provided with the experiences which 

 might bring home to his mind the immensity of time. Early man 

 himself had for his longest trustworthy chronological base line a short 

 seventy years — the span of his own existence — or at most, perhaps, a 

 hundred 3'ears, if he included the experience of his parents. Even in 

 classical times all the past was to his experience vague and indefinite. 

 He had, it is true, mythical traditions of heroic ages, golden ages, and 

 the like, but these when summed up were merel}^ the legendary total 

 of the experiences of l)ut a few generations. Bound down as Avas 

 man's mind by his anthropomorphic ideas, he naturally assigned to 

 the earth and mankind a correspondingh' brief existence; a few gen- 

 erations — a few centuries at the most — must have witnessed its birth; 

 a few generations more must ineA'itably ))ring about its death and disap- 

 pearance. Even since the invention of letters and the compilation of 

 accurate historical .records the period of time of which man possesses 

 experience, either personally or collectively, is at most a ver}^ few 

 thousands of years. It is hopeless to expect, therefore, that for a long 

 period to come the geological concept of the immensity of past time 

 will permeate the minds of the many, or that they will accept the con- 

 clusions of geology, where time is concerned, with the same confidence 

 as that with which they have long since accepted the conclusions of 

 astronom}'. 



But this intellectual backwardness of the race in the matter of the 

 appreciation of the vastness of geological time is not onl}' a stumbing 

 ])lock in the way of th(> acceptance of the results of geology among 

 the puldic at large, but :dso to tluMvorkers in other sciences, and even 

 to t\w students of geology itself. It is well within the memory of 

 many of us how even those holding the most advanced views in other 

 sciences were intensel}^ reluctant to acknowledge the possibility of the 



