544 



SCIENCE 



[N. S. Vol. XXVI. No. 669 



The work as a whole is a concise summary 

 with complete marginal references to prac- 

 tically all of the publications and conclusions 

 of previous observers on the Carboniferous 

 rooks of the Appalachian basin. It is by far 

 the most elaborate and comprehensive study 

 ever undertaken of the Appalachian Carbonif- 

 erous, and it will long remain the chief book 

 of reference for the stratigraphic relations of 

 these great series of deposits, the most impor- 

 tant economically on the continent. 



Dr. Stevenson was peculiarly qualified for 

 the great task he undertook, having himself 

 spent about forty years of his life in the 

 study of the Carboniferous rocks, and having 

 personally seen more of the Appalachian basin 

 than any other geologist. Then, too, in Dr. 

 Stevenson's library, the most complete of any 

 in publications dealing with the Appalachian 

 Carboniferous, is to be found practically 

 everything that other geologists had written. 

 The study and digestion of this immense mass 

 of data scattered through hundreds of publi- 

 cations was in itself a task of enormous pro- 

 portions, and the writer has put all of his 

 brother geologists of the present, as well as 

 those of the future, under lasting obligations 

 by the long and arduous " labor of love " in- 

 volved in the publication of this great work 

 which is destined to remain the chief monu- 

 ment of its distinguished author. 



One of the principal causes for friction 

 between the U. S. Geological Survey and the 

 other geologists of the country, not connected 

 with that organization, has been a failure of 

 the United States geologists to recognize 

 properly the work of previous observers in the 

 same area, except occasionally when these ob- 

 servers had made some glaring mistakes. The 

 absence of some such publication as Dr. Ste- 

 venson's may have been the principal reason 

 for this apparent want of courtesy and fair- 

 ness in the recognition of previous work, but 

 hereafter there can remain no "extenuating 

 circumstances " for such neglect so far as the 

 Appalachian Carboniferous is concerned. 



Eegarding the conclusions of the author 

 upon some mooted questions like the western 

 limits of the Catskill, the identity of certain 

 coal beds of wide extent, the equivalency of 



the Kanawha Black Flint, and other questions 

 of like nature, there will evidently not be en- 

 tire concurrence on the part of geologists. 

 The reviewer also thinks that the great appar- 

 ent thinning of both the Monongahela and 

 Conemaugh formations along their northern 

 and western margins is based upon mistaken 

 identifications, that while there is much thiu- 

 ning of these formations shown toward the 

 northwest, it is not really so great as indicated 

 by the author. These are minor matters, how- 

 ever, and confined to regions where, owing to 

 absence of accurate maps and careful meas- 

 urements, there is much room for doubt as to 

 identifications. 



The author rightly gives proper credit to 

 the monumental work of David White, whose 

 skillful and untiring paleobotanical studies 

 have assisted so much in the solution of the 

 many intricate stratigraphic problems con- 

 nected with the Pottsville and Kanawha for- 

 mations, and their great southwestward thick- 

 ening. 



Geologists will look forward anxiously for 

 the appearance of Dr. Stevenson's promised 

 paper upon the origin of coal and his discus- 

 sion of the many related problems for which 

 the wide study and field work of this eminent 

 teacher and geologist have given exceptional 

 qualifications. 



I. C. w. 



A General Catalogue of Doiible Stars within, 

 121° of the North Pole. By S. W. Burn- 

 ham. Part I., The Catalogue, pp. Iv -f 2Y4. 

 Part II., Notes to the Catalogue, pp. viii -1- 

 828. Published by the Carnegie Institu- 

 tion of Washington. 1906. 

 We run little risk in saying that this is the 

 most important astronomical publication of 

 the year. Although devoted to a highly tech- 

 nical division of the science, it will surely 

 command the attention of astronomers every- 

 where and long remain a reference of extraor- 

 dinary excellence. It has been many years 

 in preparation. In the introduction, the 

 author states that its first form was a manu- 

 script catalogue that he began to construct in 

 Chicago in 1870, soon after receiving his six- 



