6 EARTH FEATURES AND THEIR MEANING 



be subject to review so soon as his own horizon has been sufficiently 

 enlarged. False theories could hardly have endured so long in the 

 past, had not too great respect been given to authorities, and in- 

 dividual reasoning processes been held too long in subjection. 



The value of the hypothesis. Because all the facts necessary 

 for a full interpretation of observed phenomena are not at one's 

 hand, this should not be made to stand in the way of provisional 

 explanations. If science is to advance, the use of hypothesis is 

 absolutely essential ; but the particular hypothesis adopted should 

 be regarded as temporary and as indicating a line of observation 

 or of experimentation which is to be followed in testing it. Thus 

 regarded with an open mind, inadequate hypotheses are eventu- 

 ally found to be untenable, whereas correct explanations of the 

 facts by the same process are confirmed. Most hypotheses of 

 science are but partially correct, for we now " see through a glass 

 darkly " ; but even so, if properly tested, the false elements in the 

 hypothesis are one after the other eliminated as the embodied 

 truth is confirmed and enlarged. Thus " working hypothesis " 

 passes into theory and becomes an integral part of science. 



READING REFERENCES FOR CHAPTER I 



The most comprehensive of general geological texts written in English is 

 Chamberlin and Salisbury's "Geology" in three volumes (Henry Holt, 

 1904-1906), the first volume of which is devoted exclusively to geological 

 processes and their results. An abridged one- volume edition of the work 

 intended for use as a college text was issued in 1906 (College Geology, 

 Henry Holt). Other standard texts are : 



SIR ARCHIBALD GEIKIE. Text-book of Geology, 4th ed. 2 vols. Lon- 

 don, 1902, pp. 1472. 



W. B. SCOTT. An Introduction to Geology. 2d ed. Macmillan, 1907, 

 pp. 816. 



J. D. DANA. Manual of Geology. New edition. American Book Com- 

 pany, 1895, pp. 1087. 



JOSEPH LECONTE. Elements of Geology. (Revised by Fairchild.) 

 Appleton, 1905, pp. 667. 



A very valuable guide to the recent literature of dynamical and struc- 

 tural geology is Branner's "Syllabus of a Course of Lectures on Elemen- 

 tary Geology" (Stanford University, 1908). 



On the relation of geology to landscape, a number of interesting books 

 have been written : 



JAMES GEIKIE. Earth Sculpture or the Origin of Land-Forms. New 

 York and London, 1896, pp. 397. 



