334 NATURAL SCIENCE. Nov., 



discussed ; the teacher will do well to avoid debatable terms, or those 

 dependent on purely microscopic examination. Every encourage- 

 ment should be given to the idea that rock-specimens are parts of the 

 great masses round us, and that Geology is a study of the open air, 

 natural in the highest sense, and not an exercise in more or less 

 classical terminology. 



The modes of origin of these rocks may be described side by side 

 with their mineral characters, an amount of physical geology being 

 thus introduced to enliven the bald statement of their constitution. 

 Thus an account of modern marine shell-banks may precede the dis- 

 cussion of limestone, or may proceed naturally from the observation 

 of fossils in a rock ; while an account of the main features of an 

 active volcano will add vast interest, and even dignity, to the details 

 of a lump of basalt. 



The structures of mountains, the carving of valleys in high 

 plateaux, the rounding of pebbles, and the sifting of materials in the 

 streams, can all be illustrated by local examples, or by reference to 

 the customary excursion-resorts of the people. London and the south- 

 east of England form a district less favoured than most parts in the 

 matter of variety of structure ; yet the broad facts of physical geology 

 can even there be dealt with practically. 



But when the proofs of what were formerly called "revolutions" in 

 the surface of the globe have been made plain, and the slow and 

 gradual nature of those changes has been impressed upon the student 

 in the field, the review of the past history of life becomes the main 

 object of his study. 



For the public at large, this portion of the subject has, to my 

 thinking, the greatest educational value ; I urge, indeed, the funda- 

 mental importance of geology on account of the desirability of giving 

 everyone, from the peer to the proletariat, an outline of the history 

 of life upon the globe. 



It is impossible to disguise the fact that the teaching of 

 human history is liable to be both partial and partisan ; and that, 

 under existing systems of examination, a pupil may be well read in 

 the events of one century of the history of his own people, and yet 

 be entirely ignorant of the causes that have moulded the popular 

 opinions of his own time. Firstly, then, Geology introduces the 

 student to a history in which one is not called on to take sides, a 

 history the compilation of which is the outcome of enquiry rather 

 than enthusiasm — a remark that holds good, at any rate, until we 

 reach the Glacial Period. The pupil learns, then, the beauty of 

 facts, and that what we call truth is a conscientious and necessarily 

 imperfect deduction from them. The very imperfection of the record 

 will cause him to reason for himself, and to recognise fully the 

 difficulties of the process. Thus, perhaps, his judgment of things 

 in general will become less personal, less harsh, and less redolent of 

 the dogmatism of a " school." 



