

2 Review of Chambers's Ancient Sea Margins f 



different countries point, in many instances, to a single cause 

 operating simultaneously over distant regions. He observes: 



" There is nevertheless enough to justify a question regarding uni- 

 formity of level, not only throughout North America, but also — bold as 

 the idea, in the present state of knowledge and of hypothesis, may 

 appear — between the old and the new continents. It has certainly ap- 

 peared to myself, to say the least, as a promising prognostic of some 

 important new views regarding a chapter in the past history of* the 

 globe, when, it being granted that terraces and benches of land are 

 marks of ancient levels of the sea, I find that a tendency to a bench 

 form or plateau, at 60, or from 60 to 70 feet above present high water, 

 exists on the coasts of the United States and in the Gulf of St. Law- 

 rence, as it does in Britain ; that conspicuous terraces in Britain and in 

 France at 188 and 392 feet, are repeated in America ; that there, also, 

 at about 545 feet, are several repetitions of a decided and most notable 

 Scottish terrace — that Scott built his house of Abbotsford on an ancient 

 sea-beach beside the Tweed, which finds an analogue in the first of the 

 grand ridges sweeping from east to west behind Toronto; and that the 

 sandy plateaux of Lanark and Carstairs are in melrical harmony with 

 the terraces and ridges of the half-peopled wilds of Michigan.'" — p. 316. 



This must be viewed as a bold inference, and should not be 

 admitted without extended investigation. It is certainly a legit- 

 imate subject of enquiry, and one of the grandest in its range, 

 before the geologist If proved; it declares that the causes of 

 variation in the water line, in the recent history of the globe, 

 have acted at certain periods as widely as the ocean. If dis- 



roved, the facts indicate changes no less extensive, which have 



een produced at different epochs for different regions, and they 

 show a still greater instability in the earth's surface, telling of 

 oscillations in its various parts continued through ages since the 

 tertiary epoch, until a whole continent has been terraced in all 

 its valleys.* 



# In connection with the subject of terraces, we add a remark here on the word 

 drift, as it is often used. It is frequently applied to any loose material on the sur- 

 face, not originating where found, whether stratified or unstr citified . This name be- 

 ing affixed to any accumulations, one or another drift-theory comes in to account for 

 the facts, — such as the currents and icebergs of an ocean over the submerged lands, 

 the action of waves of translation, or the movement of glaciers. The term in its 

 very nature implies a theory of this general character. But there is much mate- 

 rial of the kind called drift, which ma 1 



ay be of sea-shore or beach accumulation ; 

 there is much also which may be of river origin, and much that may be lacus- 

 trine. Instead of determining by observation the actual facts in the different 

 cases, and carefully discriminating, the mind is led away by the term drift at once 

 to prejudge, to the confusion and error of observations. In its general signifi- 

 cation, it had better therefore be rejected ; such truthful terms as earth, sand, gravel, 

 day, boulder accumulations, are preferable, until it is fully determined that the ma- 

 terial in any case is true drift, and not alluvial, lacustrine, or of beach or seashore 

 origin. First prove it to be drift (often a difficult problem) and then so designate 

 it, is a safe rule. 



We have been led into these remarks by observing not unfrequently, that river 

 terraces and beach deposits were ranked with the drift; and when once so-called, 

 every succeeding step in investigation leads into deeper error. 



