64 Scientific Intelligence. 



petrology has received in the last ten years is nowhere more clearly 

 to be perceived than in the increased size of this new edition of 

 Prof. Rosenbusch's well known work over that published in 1887. 

 And this increase marks well the incessant activity of the author 

 in the coordination of the vast mass of material which has been 

 published since that date. 



It is needless to say that the appearance of this work will be 

 greeted with the keenest interest by all petrographers. No one 

 has held a more commanding position in this branch of science 

 than the author, and no one has exerted a greater influence in its 

 development through his pupils, especially in this country, from 

 which they have been largely drawn. 



It would, therefore, be a matter of interest to present a full 

 review of its contents, but in the brief limits of this notice of its 

 appearance it is only possible to say that the work is kept strictly 

 within the limits set in the former editions, that is, to the micro- 

 scopical physiography of the igneous rocks ; general petrology and 

 chemical and geological relations being confined by brief mention 

 within the smallest possible limits, while the author's views are 

 often hinted at rather than actually expressed. 



The ideas which the author has advanced during recent years 

 upon the classification and relationships of igneous rocks in various 

 brief publications are here affirmed and their influence is everywhere 

 observable upon the subject-matter of the work. The course laid 

 down in the past is here steadily pursued to a logical conclusion. 



In his preface the author states that he still retains the division 

 of the extrusive rocks into two groups dependent on geological 

 age, though it is clear from his remarks that he would prefer to 

 do away with it. 



The present half of the work comprises the plutonic rocks ("tief 

 engesteine") and the "dike rocks" (" ganggesteine"). Among 

 the latter, as must be expected, we find a considerable number of 

 new types and names expressed. 



We note with regret that the author has felt obliged to confine 

 the work so strictly within the limits mentioned above. Analy- 

 ses of the types described would have added greatly to the 

 convenience and value of the work. We trust that the author 

 may see his way in the future to supplement this work by one deal- 

 ing with the many phases of petrology, either wanting or all too 

 briefly expressed in this volume. Its appearance would certainly 

 be received with the greatest interest by all workers in this branch 

 of science. L. v. p. 



8. The Rubies of Burma and Associated Minerals — their 

 Mode of Occurrence, Origin and Metamorphoses. A Contribu- 

 tion to the History of Corundum. By C. Barrington Brown 

 and J. W. Judd. — An abstract of the paper bearing this title is 

 given in a recent number (No. 345) of the Proceedings of the 

 Royal Society. It details the investigations carried on in the field 

 under the auspices of the government by Mr. Barrington Brown 

 and also the results of a penological and mineralogical examina- 



