THE STARTING-POINT 



may appear more than once, but from different points of view, 

 since it is often useful to contemplate certain features of the 

 landscape from more than one place of observation. 



To drop the figure, the reader will find in these papers, in a 

 plain and popular form, yet it is hoped not in a superficial 

 manner, some of the more important conclusions of a geo- 

 logical worker of the old school, who, while necessarily giving 

 attention to certain specialties, has endeavoured to take a 

 broad and comprehensive view of the making of the world in 

 all its aspects. 



The papers are of various dates ; but in revising them for 

 publication I have endeavoured, without materially changing 

 their original form, to bring them up to the present time, and 

 to state any corrections or changes of view that have com- 

 mended themselves to me in the meantime. Such changes or 

 modifications of view must of necessity occur to every geologi- 

 cal worker. Sometimes, after long digging and hammering in 

 some bed rich in fossils, and carrying home a bag laden with 

 treasures, one has returned to the spot, and turned over the 

 debris of previous excavation, with the result of finding some- 

 thing rare and valuable, before overlooked. Or, in carefully 

 trimming and chiselling out the matrix of a new fossil, so as 

 to uncover all its parts, unexpected and novel features may 

 develop themselves. Thus, if we were right or partially right 

 before, our new experience may still enable us to enlarge our 

 views or to correct some misapprehensions. In that spirit I 

 have endeavoured to revise these papers, and while I have 

 been able to add confirmations of views long ago expressed, 

 have been willing to accept corrections and modifications based 

 on later discoveries. 



In the somewhat extended span of work which has been 

 allotted to me, I have made it my object to discover new facts, 

 and to this end have spared no expenditure of time and 

 labour ; but I have felt that the results of discoveries in the 



