FROM KNOWN TO UNKNOWN 3 



Geology. 



In their researches on the crust of the earth Playfair, Hutton 

 and Lyell did not pursue them by going down a coal mine till they 

 came to the lowest available beds and work upward from these 

 to the highest. Though for purposes of exposition a great geologist, 

 as Sir Archibald Geikie, may expound the making of the earth 

 from the lowest to the highest levels, and Professor Bonney tell 

 us the Story of our Planet from beginning to end as if he had watched 

 it unfolding, Lyell in his Principles of Geology shows how the 

 studies of his great province began. There we have the backward 

 reading of its story pursued by himself and other great ones, and 

 where it led them. Commencing with the Pleistocene period 

 and passing through Xeocene and Eocene periods through the 

 Mesozoic Era and its cretaceous, Jurassic and triassic systems to the 

 Newer Palaeozoic Era and its Permian, carboniferous, and Devonian 

 systems, the older Palaeozoic Era and its Silurian Ordovician and 

 Cambrian systems, he reaches the unknown. But before all this 

 patient research and its record is reached he treats, as he must, of 

 consolidation and alteration of strata, of petrification of organic 

 remains, elevation of strata, horizontal and inclined stratification, 

 of faulting, denudation, upheaval and subsidence as they combine 

 to remodel the earth's crust. The title of his classical work is 

 significant — An Attempt to Explain the Former Changes of the 

 Earth's Surface by Reference to Causes now in Operation (it 

 may be noted that in 1830 they were fond of capital letters and 

 of underlining their words). If these great men had been con- 

 demned to the sole use of the method of the annalist in his treatment 

 of human history, that of the coal mine in geology, this great 

 province of knowledge would never have been what it is to-day. 



At this point I think it well to state that this illuminating 

 principle of Lyell is pursued in nearly all the matters of fact and 

 their interpretation contained in the following chapters, so that 

 from time to time I shall have to employ the verb, coined for the 

 purpose, when I attempt to " Lyell " them on behalf of Lamarck 



Anthropology. 



The anthropologist could hardly make a start with his research, 

 if, knowing nothing of his own anatomy, physiology, customs and 

 beliefs, he tried to interpret the physical features, habits, manners, 

 customs and rites of an African tribe. Without such prior know- 

 ledge he would find it a profitless task to journey to the banks of 

 the Zambesi and bring back any intelligible history of the aborigines. 

 If he did not know the games of a European child how could he 



b2 



