168 GEOLOGICAL HISTORY. 



CHAPTER VII. 

 GEOLOGICAL HISTORY. 



THE natural history of the land which is now Yorkshire goes 

 very far back beyond the remotest point of time which can be 

 assigned or conjectured for the first appearance of its human 

 inhabitants. Still farther back we seek the geological history 

 of the successive steps by which the ancient ocean gave birth 

 and place to that land. There is an immensity of the past 

 during which the forces of nature were employed by the Ruler of 

 Nature in preparing a suitable place for the comfortable existence 

 of intelligent men, even as there is an immensity of the future, 

 in which we may hope that existence will be prolonged, that in- 

 telligence enlarged. 



Even as the life of an individual man occupies but a small 

 space on the scale of time which measures the duration of his 

 race, the whole period during which mankind have existed on 

 the earth is but a small part of the slowly elapsed ages of 

 nature. If history enables us to measure back with confidence 

 a hundred generations of men without reaching the origin of 

 the human race, geology recalls to our view many successive 

 assemblages of organic life in which man had no part, and which 

 followed one another after intervals of time immensely longer 

 than those which separated Sesostris and Alexander ; Nearchus 

 and Columbus; the advent of Caesar and the Conquest of 

 William. 



How much longer we cannot say ; for the great periods dis- 

 closed by geology are of a different order from those measured by 

 chronology; they are the durations of distinct systems of life, 

 suited to peculiar conditions of nature, and can only be faintly 

 illustrated by the extinction of feebler tribes like the Red Men 



