RECORDS 49 



did not attract him much, after all his preparation, and in 1752 

 he went to Norfolk to learn agriculture. There his mind first 

 turned definitely to mineralogy and geology. In 1754 he set- 

 tled on his ancestral estates in Berwickshire, where he remained 

 fourteen years, with occasional visits to Edinburgh and more 

 distant parts of the kingdom. In 1768 he gave up country 

 life and removed to Edinburgh to devote himself entirelv to the 

 study of geology and kindred sciences. His untiring industry 

 enabled him to accomplish a marvelous amount of work in 

 chemistry and finally to elaborate his essays in geology, revo- 

 lutionizing that science and, with the elucidation given his work 

 by Playfair's " Illustrations of the Huttonian Theory of the 

 Earth," raising it to the high plane which it has occupied ever 

 since. Modern geology dates from the publication in the spring 

 of 1802 of John Playfair's explanation, elaboration and defense 

 of Hutton's theories. 



Professor Dodge, in his memorial of Playfair, said in brief : 

 To James Hutton we owe many fundamental truths now rec- 

 ognized in physiography, and to John Playfair we owe the eluci- 

 dation of these ideas, and their amplification. 



The doctrine that rivers are the cause of their valleys, and 

 the proof thereof is perhaps the most important foundational 

 idea that we owe to the combined labor of these two geological 

 worthies. Playfair's clear exposition of the possible origin oi 

 river terraces, his acute description of the relation of lakes to 

 rivers, his analysis of the varied forms of shore-lines, and his 

 emphasis of the importance of initial shore-lines, all clearly ex- 

 ploited in his illustrations, deserve to take rank with the much 

 quoted passage on rivers and their valleys, as being accepted 

 geographical truths far in advance of their time. 



Summary of Papers. 



Richard. E. Dodge, Ax Interesting Landslide in the 

 Chaco Canon, New^ Mexico. 



On a high mesa to the southeast of the Chaco Canon, and 

 about four miles below Putnam, New Mexico, is a series of 

 stone monuments about fiv^e feet high and four feet in diameter. 



