Conclusion 289 



entirely erroneous in the next. Every year, however, the 

 data on which these inferences are based are more 

 thoroughly comprehended and more rigidly tested. Geo- 

 logy now possesses a large and ever-growing body of well- 

 attested fact which will be destroyed by no discovery of 

 the future, though it will doubtless be vastly augmented, 

 while new light may be cast on many parts of it now 

 supposed to be thoroughly known. 



Each of us has it in his power to add to this accumula- 

 tion of knowledge. Careful and accurate observation is 

 always welcome, and may eventually prove of signal 

 importance. We must be on our guard, however, against 

 premature speculation and theory. Let us do our utmost 

 to eliminate hypothesis from our gathering of facts, or at 

 least clearly to distinguish between what is fact and what 

 may be our own gloss or interpretation of it. And, above 

 all, let us preserve the modesty of the true student, face to 

 face with the mysteries of nature. Proving all things and 

 holding fast that which we believe to be true, let us look 

 back with gratitude and pride to what has been achieved 

 by our forerunners in the race, and while we labour to 

 emulate their devotion, let us hold high the torch of 

 science, and pass it on bright and burning to those who 

 shall receive it from our hands. 



