424 



SCIENCE. 



[X. S. Vol. XXI. Xo. 5.33. 



the Harvard College Observatory, and will 

 put the lists of known maxima and minima 

 in the convenient shape of tables. While 

 the former catalogue will make a volume 

 of about 500 pages (quarto size), the latter 

 will only have one third of this bulk. Both 

 catalogues will be a very valuable accession 

 to our literature on this subject. 



Useful Work for a Small Equatorial— A 



Proposed Discussion. 



The discussion was opened by Professor 

 Edward C. Pickering. He stated that 

 measurements of wide double stars might 

 be useful, but that the positions of stars 

 much more than 5" apart could be better 

 determined by photography, while closer 

 stars required a large telescope. The' 

 brightness of stars can now be readily and 

 inexpensively determined with a wedge 

 photometer, and the relative light of the 

 components of close doubles by a polarizing 

 photometer. The Herschel-Argelander 

 method could be usefully applied to faint 

 stars, especially to the components of coarse 

 clusters, and to Durchmusterung zones, 

 inserting all stars brighter than a fixed 

 magnitude. Variable stars of long period 

 can be usefully followed by inexperienced 

 observers, since the range is large. Obser- 

 vations of suspected variables, of Algol, 

 and other short period variables, are likely 

 to be of little value, except when made by 

 observers having long experience. Biat 

 little useful work could be done with 

 speetroscopas attached to small telescopes. 

 A search for new stars in the Milky Way, 

 and an examination of known nebulae to see 

 if they are gaseous, as was, perhaps, first 

 done by Col. John Herschel, might prove 

 of value. 0})s('rvations of Ju])iter"s satel- 

 lites, comets, sunspots and solar promi- 

 nences were also mentioned as useful fields 

 of work for instruments of this class. 



Frank B. Littell, 

 For the Council. 



SCIENTIFIC BOOKS. 

 Die Moore der Schweiz, mit BeriXcksichtigung 

 der ge^amten Moorfrage. Von Dr. J. Fruh 

 und Dr. C. Schroter. (Beitrage zur Geol- 

 ogic der Schweiz, lierausgegeben von der 

 geologischen Kommission der Schweiz, na- 

 turforschenden Gesellschaft, geotechnische 

 Serie, III Lieferung.) Bern, 1904. 4°, 

 pp. xviii -j- 7.51. 45 text-cuts, 4 plates and 

 a map. 



Probably every person seriously interested 

 in peat-bogs (or, as we may better call them, 

 peat-moors), whether it be from a geological, 

 a x^hy to-ecological or an economic standpoint, 

 has known that the present work was in prep- 

 aration and has eagerly anticipated its appear- 

 ance. The authors are well known as among 

 the foremost authorities upon the subject, and 

 their work now before us fully satisfies our 

 high expectations. While primarily devoted 

 to the study of the Swiss moors, the authors 

 nevertheless discuss every question also from 

 the general or world standpoint, so that the 

 work as a whole is in reality a study of peat- 

 moors based upon those of Switzerland as 

 tyjics. It is divided into two parts, a first 

 devoted to Moor-questions in general (435 

 pages), and a second given to a systematic 

 description of those of Switzerland (310 

 l)ages). Under the first part is discussed, the 

 general nature and place of moors, peat-build- 

 ing plant-groups (a modern ecological study), 

 peat and its nature, geology of moors, geo- 

 graphical distribution of moors, a geomorpho- 

 logical classification of the moors of the world, 

 nomenclature in relation to physical features, 

 agricultural conditions of the Swiss moors, 

 post-glacial vegetation history and its recon- 

 struction through moors. Every chapter is 

 characterized by exhaustive but clear treat- 

 ment, by copious citation of literature, in- 

 cduding that of this country, and by appro- 

 priate illustration. Among the illustrations 

 are many of those diagrammatic vegetation 

 cuts now coming -into vogue in ecological 

 works, while the plates include two tjiiical 

 photographic moor-scenes, of which we could 

 wish there were many more. It is impossible 

 here to particularize farther, and it must suf- 

 fice to say that this work is incomparably the 



