Geology and Mineralogy. 169 



erosion, the Appalachian range would be an example of an anti- 

 clinorium. The Sierra Nevada, when its rocks were crushed and 

 folded at the close of the Jurassic, was a synclinorium. The 

 broad uplift in Tertiary time of the broken arch whos.e abutments 

 remain in the Sierra Nevada and the Wasatch, was an example 

 of an anticlinorium. 



The two words, as thus used by Professor Dana, seem perfectly 

 appropriate to the significations which he assigned to them, and 

 they seem to me to be still desirable terms in their original sense. 

 Even those who do not accept Professor Dana's theoretical views 

 in regard to the dynamics of mountain-making, must recognize 

 the two types of mountain structure, as corresponding to two 

 different processes of formation. The same distinction between 

 the two types of mountain ranges has been recognized by Pro- 

 fessor Le Conte,* but the designations which he proposes for 

 them seem far less elegant and appropriate than those proposed 

 by Professor Dana in the article in question. The word " syn- 

 clinorium " is used by Professor Dana in the last edition of his 

 Manual of Geologyf in precisely the same sense in which it was 

 proposed in 1873. 



The nomenclature proposed by Professor Van Hise is there- 

 fore objectionable, as involving a transfer of words which are 

 still desirable in their original sense to an entirely different mean- 

 ing. Moreover, the derivation of these words from the Greek 

 opo'i which made them etymologically so elegantly appropriate 

 in Dana's original use^ seems to have no special appropriateness 

 for the sense in which it is now proposed to use them. The 

 masterly character of Professor Van Rise's article will undoubt- 

 edly give it a great influence over the thought and language of 

 all students of Physical Geology. That it should lead them to 

 the adoption of a nomenclature so objectionable, seems an event 

 greatly to be deprecated. w. isr. r. 



2. Transactions of the Geological Society of South Africa. 

 Vol. I, March 1, 1896 ; II, pts. 1 and 2, February and March, 

 1896. Johannesburg. Edited by the Secretary, David Draper, 

 F.G.S. — Some of the papers, given in these transactions, the pub- 

 lication of which has been recently commenced, are as follows : 

 The primary system of South Africa with special reference to the 

 conglomerate beds of the Witwatersrand by David Draper ; on 

 the economic importance of the Murchison Range by C. Wilson- 

 Moore ; on Kimberley and its diamonds by W. Guybon 

 Atherstone. 



3. The Rubies of Burma. — In the January number of this 

 Journal (p. 64) extensive quotations are given from the abstract 

 of a most interesting paper by C. Barrington Brown and J. W. 

 JuDD on the rubies of Burma and the associated minerals, their 

 mode of occurrence, origin and metamorphoses. Those interested 

 will be glad to learn that the full memoir has now been published 

 in vol. clxxxvii, pp. 151-228 of the Philosophical Transactions. 



* Elements of Geology, Third Edition, pp. 264-266. 

 f Manual of Geology, Fourth Edition, p. 380. 



