November i8, 1887.] 



SCIENCE. 



249 



with the naked-eye estimation of their .serial magnitudes, to find 

 what is the relation between the two series ; i.e., as the magnitudes 

 increase by apparently equal intervals of brightness, how do the 

 measured illuminating-powers increase .' He finds, that, as the 

 psychophysic law requires, the latter increase by a constant ratio, 

 but that this ratio is not exactly constant, but decreases slightly 

 (according to a formula given in the paper) with the brightness of 

 the stars. 



The critical portion of the journal will perhaps arouse more com- 

 ment than the original part, because it comes more in conflict with 

 current views on psychological topics. While not taking an ag- 

 gressive tone, the policy of the journal is evidently to plainly and 

 forcibly state the broader inferences upheld by a technical study of 

 mental facts, and, if necessary, to fearlessly combat views opposed 

 to or neglecting such considerations. The able detailed review of 

 the work of the English Society for Psychic Research is sure to 

 attract attention. The point of view is decidedly negative. The 

 evidence in favor of ' telepathy ' is regarded as entirely inconclusive 

 by lack of a host of necessary precautions, as well as a considera- 

 tion of other modes of explanation. It is an aspect of the question 

 the importance of which will be more and more generally recognized 

 as the first gust of enthusiasm excited by apparently wonderful re- 

 sults subsides. A review of the psychological text-books of Pro- 

 fessors McCosh, Bowne, and Dewey is a destructive criticism of the 

 standpoints from which these writers set out, while Professor 

 Ladd's ' Physiological Psychology ' receives very just proportions of 

 praise and blame. 



In addition to this, there is a review of the ' brain-localization ' 

 question by Dr. Starr, of Mr. Galton's views on the persistency of 

 type by Professor Brooks, of Delage's researches on the functions 

 of the semicircular canals by Professor Sewell, and a note on logi- 

 cal machines by Mr. C. S. Peirce, together with a large number of 

 useful minor reviews and notes. An undue number of misprints 

 disfigure some of the pages. 



Greeko-Slavonic Literature. By M. Gaster. London, Triibner. 

 8". 



The importance of researches on the growth of folk-lore is more 

 and more recognized. While in the early times of this study the 

 lore of each nation was considered as an outcome of its ancient 

 mythology, later on the interdependence of the traditions of nations 

 widely separated in space and time was more clearly understood, 

 and researches on the origin and migration of legends became of 

 greater inaportance. While this historical point of view is the lead- 

 ing one in the inquiries of most students, the psychological char- 

 acter of each nation as influencing its folk-lore must not be disre- 

 garded. The present volume treats of the connection between 

 European folk-lore and the early literature of Slavonic nations. 

 The author treats first of the influence of Bogomilism upon the 

 religious literature which later on became folk-literature of the 

 European nations. He traces the latter back to Greek texts which 

 came to Constantinople from the east, and passed thence to the 

 Bogomils. A second source, equally Oriental in its origin, was sup- 

 plied by Jewish legends. He discusses the Apocrypha of the Old 

 and New Testaments in its influence upon European literature, and 

 shows in a few instances the interesting phenomena of their tran- 

 sition from tales into ballads, and from ballads into lyrics, in which 

 the name of the hero disappears gradually, and a personal song is 

 changed into a general impersonal one. The author finds in the 

 belief of witchcraft in the Graal legend and other traditions, not those 

 relics of hoary antiquity which they are generally considered, and 

 as which they have become the object of a reconstructive mythol- 

 ogy, but a result of the Christian legends and myths, which be- 

 came the property of the people at a comparatively recent date. In 

 discussing the origin of the romantic literature, Gaster favors the 

 opinion that it was also introduced into Europe by the Slavonic 

 nations, and rejects Benfey's theory that it was communicated to the 

 western people by the Mongolians. In an appendix Gaster tries to 

 solve the problem of the origin of the Glagolitic alphabet, and 

 shows that a connection with the Armenian alphabet is at least 

 probable. The whole volume is an extremely interesting study of 

 the growth of folk-literature, and shows how intricate the channels 

 are from which its sources flow. Great care must be taken in treat- 



ing questions of this kind, particularly among nations which have 

 no literature, where historical facts, upon which the study must be 

 founded, are entirely wanting. Particularly in this case rash con- 

 clusions must not be made until we are better acquainted with the 

 psychological laws of the growth of folk-lore. The historical 

 method as applied by Gaster is the only one that can lead to 

 satisfactory results, but it must be supplemented by an inquiry into 

 the assimilation of legends by different nations and their blending 

 with the more ancient stock of folk-lore. The latter point has 

 been disregarded by the author, and therefore some of his conclu- 

 sions on the Oriental origin of certain legends cannot be accepted 

 until fuller proof is given. 



An Elementary Treatise on Analytical Mechanics. By WIL- 

 LIAM G. Peck. New York, Barnes. 12'='. 



This is, as its title implies, an elementary treatise on the subject 

 named, and is of substantially the same character as the majority 

 of works of similar purpose, intended for the introduction of the 

 student into the study of analytical mechanics. Dr. Peck, however, 

 has the advantage, as an author, of having had an unusually ex- 

 tended and very fortunate experience in teaching, and his book may 

 be taken as the embodiment of so much of the subject as he has 

 found the average college-man capable of taking up during the 

 average college course of advanced mathematics. It is intended, 

 as stated in the preface, to include all the principles needed by stu- 

 dents in technical courses of study, and the calculus is used to a 

 moderate extent in their development. 



This work is by no means such a treatise as that of Bartlett, and 

 is necessarily given a much more condensed and less logical form. 

 It covers, however, the full range of work which the student can be 

 ordinarily expected to take, and it may be made to pave the way 

 most satisfactorily to the use of advanced treatises and the works 

 on applied mechanics which are now studied in the best technical 

 schools and schools of engineering. Its accuracy is vouched for by 

 the reputation and experience of its author, and its plan may be 

 seen by inspection to be good and satisfactorily complete. Kinet- 

 ics and the doctrine of energy are given the place to which they are- 

 entitled, — a place denied them in books following the older writers 

 on this subject. We should suggest that the discussion of the 

 mechanics of gases and vapors might be enlarged profitably by the 

 introduction of the pure thermodynamics of the subject, and that 

 the last chapter, that on machines, might be improved by the re- 

 vision of the descriptive matter, and by a study of modern exam- 

 ples of such apparatus. No criticism lies against this work espe- 

 cially ; but it is time that all these elementary treatises on this sub- 

 ject were pruned of their antique illustrations, — the compound 

 balance, for example, — and modern sketches substituted, such, for 

 example, as Dr. Peck gives us in his article on the rotary-pump. 

 On the whole, this book is one of the very best of its class; and the 

 writer has found, by experience in its use, that it is a most excellent 

 text-book. 



NOTES AND NEWS. 

 The account of the recent trial in England of the Spanish 

 cruiser ' Reina Regente,' resulting in the development of a speed 

 of 20.6 knots over a measured mile, has been received with keen 

 interest at the Navy Department, where every effort has been made 

 to design vessels of like high speed to meet the demands of Con- 

 gress. The number of war-ships able to make above 19 knots is 

 much smaller than is commonly supposed, and, in fact, the records 

 of the department show that but two other vessels have been able 

 to attain that speed. These are the ' Dogall,' built in England for 

 the Italian Government, which made one run over a measured mile 

 at the rate of ig.66 knots per hour; and the 'Orlando,' built by 

 private contractors for the English Government, which made one 

 run at the rate of 19.25 knots per hour. It is said at the depart- 

 ment that these two vessels, together with the ' Reina Regente,' 

 are the outcome of efforts to reach 19 knots, running through many 

 years ; and the small measure of success attained renders it unsafe 

 to guarantee so high a speed for the cruisers now building, and 

 known as the 19-knot cruisers. 



— A complete list of the papers presented at the meeting of the 

 National Academy of Sciences, held at Columbia College, New 



