396 Scientific Intelligence. 



The present volume contains the detailed description of collec- 

 tions made from these rocks since 1871. h. s. w. 



3. Elements of Geology : A text-book for colleges and for the 

 general reader ; by Joseph LeConte, revised and partly rewrit- 

 ten by Herman LeRoy Fairchild. 5th edition, revised and 

 enlarged. 6(^7 pp., 1002 figs. 1903. (D. Appleton & Co.)— The 

 revising author makes special mention of the adoption in this 

 volume of Professor Chamberlin's Planetesmal Hypothesis of the 

 Origin of the Earth, stating that "recent studies discredit the 

 nebular hypothesis " which has long held a prominent place in 

 geology. Other new points of view resulting from the general 

 progress of science are noted, and the illustrations are augmented 

 by a number of original views reproduced by photography of 

 typical geological features, and, as is stated in the reviser's 

 preface, "the spirit and style of the revered author have been 

 held as the model," and successfully. h. s. w. 



4. Chemical Analyses of Igneous Rocks / Published from 

 188Jf-1900^ with a Critical Discussion of the Character and Use 

 of Analyses ; by H. S. Washington. U. S. Geol. Surv. Prof. 

 Paper 14, Washington, 1903, 4°, 495 pp. — This is a publication 

 w^hose appearance will be gladly welcomed by petrographers, 

 chemists and geologists interested in the chemistry of rocks. 

 Since the time of Koth, whose collected tables were so long an 

 invaluable aid in petrographic investigations, no such adequate 

 collection as the one before us has appeared. The w^ork begins 

 Avith a discussion of the methods of making analyses and a just 

 emphasis is laid upon the considerable amount of poor or incom- 

 plete work which is often done in this direction. A basis for the 

 rating of analyses according to their completeness and accuracy 

 is described and all of those in the tables are rated according to 

 the standards adopted. Following this method the whole num- 

 ber is divided into two sets of tables — " superior analyses," of 

 which 1987 are given, and "inferior analyses," of which there are 

 984. The superior analyses are classified according to the new 

 quantitative system recently proposed by Cross, Iddings, Pirsson 

 and Washington, and thus serve as a most complete exposition of 

 this system. In all these cases the calculated " norm " of the 

 system is given with each analysis. The inferior analyses are 

 classified according to prevailing systems, that is they are grouped 

 under the names with which they have been published. With 

 all analyses the locality of the rock, the name of the analyst and 

 the reference in the literature are given, and usually some 

 appended remarks containing useful information. The accom- 

 panying text contains also an interesting discussion of the infor- 

 mation thrown on the new system of classification by the gen- 

 eralized facts which the collection affords. The whole evinces the 

 results of a vast amount of patient and unwearied industry in 

 the search throuMi the literature and in the collatino- and reduc- 

 ing to form of the material collected. Its vahie is greatly 

 enhanced by a very complete system of indexes, to new rock 

 names, to old rock names, to localities, to the text, and there is 



