OCTOBEE 12, 1917] 



SCIENCE 



365 



hardly seem fitted for popular perusal, and yet 

 so clearly are the fundamental principles 

 treated that any intelligent man, or high-school 

 scholar, for that matter, would hardly fail to 

 be understandingly interested in the applica- 

 tion of these principles to important facts of 

 every-day life. The consideration of catalysis 

 leads to its application in the manufacture of 

 sulfuric acid and the hardening of fats, and to 

 some of the facts concerned with digestion; in 

 connection with electricity are discussed the 

 refining of metals, the manufacture of chlorin 

 and caustic soda, and many electric-furnace 

 products; the colloidal state is illustrated by 

 photographic plates, the sedimentation of 

 rivers, plasticity of clay, dyeing and water and 

 sewage purification. Perhaps the most interest- 

 ing chapter is that concerned with the fixation 

 of nitrogen, particularly applicable to the de- 

 mand, both for munitions and for fertilizers, 

 at the present time. Other chapters are " Com- 

 bustion, and the production of fire," " The 

 chemistry of illuminants," " Energy, fuel and 

 explosives," " Cellulose and cellulose products," 

 " Glass, soda, soap," and " Synthetic chemis- 

 try." All are exceedingly readable, and are to 

 be recommended, not only to the man who de- 

 sires to get a glimpse of what modern chemis- 

 try is doing for the comfort and needs of life, 

 but quite as well to the first-year student of 

 chemistry, in school or in college, who has far 

 too often come to regard the study as a mass 

 of unconnected facts and abstruse theories, 

 mingled with a mess of dirty test tubes and 

 beakers. In this book one gains a glimpse of 

 the beauty of it all, if indeed one has any com- 

 prehension of beauty. 



One word remains to be said. Many of us 

 were trained in our earlier years to believe that 

 for the past half century all chemistry was 

 " made in Germany," and in this there was far 

 more of truth than of fiction. And yet it is 

 hardly an exaggeration to say that in Eng- 

 land, America and France more progress has 

 been made in the past thirty-six months than 

 had been made in Germany in the previous 

 thirty-six years. Perhaps the same has been 

 true of Germany; our information regarding 

 this is meager. As never before, chemistry is 



" coming to her own," and hence the timeliness 

 of Dr. Findlay's " Chemistry in the service of 

 man." Jas. Lewis Howe 



Washington and Lee XJniversitt 



Ulugh Beg's Catalogue of Stars. By Edward 



Ball Knobel. Carnegie Institution of 



Washington, Publication 'No. 250. 1917. 



Pp. 109. 



Mr. Knobel's compilation of Ulugh Beg's 

 Catalogue forms a fitting sequel to Ptolemy's 

 Catalogue of Stars, also edited by Mr. Knobel 

 in conjunction with Dr. C. H. F. Peters. 

 Ulugh Beg, born in 1394, succeeded his father 

 as ruler of Persia in 144Y. Two years later 

 he was killed by his son. He devoted much 

 of his time to astronomy, was the founder of 

 an observatory at Samarkand, which is located 

 in the southern part of Russian Turkestan, 

 and in the year 1437 published a catalogue 

 of stars. 



Such catalogues furnish at best only rough 

 determinations of stellar positions because of 

 a number of causes. To add to the insecurity 

 of the positions, it is not always certain whether 

 all the stars of such a catalogue have been 

 directly observed by the author, or whether, 

 for the sake of completeness he has added star 

 positions determined by predecessors, and re- 

 duced to the epoch of his own catalogue in a 

 manner unrecorded. Added to this is the 

 doubt whether the manuscripts available con- 

 tain a true record of the original catalogue. 



While it is eminently worth while to pre- 

 serve such a catalogue, if only for historica' 

 purposes, great care should be taken not to 

 place too great dependence upon its star posi- 

 tions. 



Mr. Knobel has apparently made a thorough 

 investigation of the subject. In addition to 

 the catalogue proper he has included a com- 

 parison of Ulugh Beg's star positions with 

 positions reduced from Piazzi's catalogue, 

 with the exception of 300 stars whose posi- 

 tions were reduced from the catalogues of 

 Danckwortt and Neugebauer. Following the 

 comparisons he has collated the manuscripts 

 which were examined, and closes the volume 

 with a vocabulary of Persian words prepared 



