Editorial. 



At the recent meeting of the British Association for the 

 Advancement of Science in Nottingham, the section devoted to 

 geology was perhaps the busiest department of the association. 

 Contributions covering nearly all phases of the science crowded 

 the time allotted to the reading of papers. Among them petrol- 

 ogy held a prominent position, owing to the eminent character 

 of the president of the section, and to his successful labors in 

 this branch of geology. Mr. Teall based his presidential address 

 upon the data furnished by petrological research, which, to his 

 thinking, lend additional strength to the uniformitarian doctrines 

 of Hutton. By a variety of illustrations he showed the identity 

 of ancient and modern rocks, whether sedimentary, igneous, or 

 metamorphic, and inferred a similarity of physical conditions 

 attending their formation. He emphasized the high degree of 

 differentiation of organic life at the time when the first Cambrian 

 strata were deposited, and maintained that the crystalline schists 

 of earlier age, so far as we have yet become acquainted with 

 them, do not contain the records of the early stages of the 

 planets' history. They can not be considered to represent the 

 primitive crust of the earth. His testimony as to the identity of 

 the volcanic lavas erupted in Paleozoic and Tertiary times in 

 Great Britain, both as regards their structure and composition, 

 allowance being made for subsequent alteration, is signi- 

 ficant. It shows that in this region, through a long succession of 

 ages, the groups of rock magmas developed in different periods 

 of volcanic activity have been similar, and that the essential 

 character of the petrographical province did not change. 



Sir Archibald Geikie's paper, " On Structures in Eruptive 

 Bosses which Resemble those of Ancient Gneisses," was a valuable 



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