374 



THE POPULAR SCIENCE MONTHLY. 



how to beget and perpetuate the best stock. 

 Any thing that incites thougiit and action 

 in this direction must advance agriculture 

 and lay more deeply and broadly some of 

 the foundations of national wealth. As Dr. 

 Sturtcvunt's treatise is of this nature, and 

 is eminently philosophical and scientific, it 

 deserves well of all interested in this class 

 of subjects. Its teachings, if generally 

 understood, will lead to intelligent action 

 in a line in which at present too much is 

 left to lucky accidents. 



Memoirs of the Royal Astronomical So- 

 ciKTY. Vol. xl. A Catalogue of 10,300 

 Multiple and Double Stars, arranged in 

 the Order of Right Ascension by the 

 late Sir J. F. W. Herschel, Bart., and ed- 

 ited by the Rev. R. Main, M. A., F. R. S., 

 Radcliffe Observer, and the Rev. C. 

 Pritchard, M. a., . R. S., Savilian Pro- 

 fessor of Astronomy in the University 

 of Oxford. London, ISH. 



In 1863 Sir John Herschel completed a 

 descriptive catalogue of all the nebulfe and 

 clusters known up to that time, the greater 

 portion of which had been discovered by 

 his illustrious father. Sir William Herschel, 

 and by himself. This was a most valuable 

 and complete compilation, and, although 

 containing a list of no less than 5,079 neb- 

 ulae and clusters, it is singularly free from 

 errors. This, no doubt, was in great part 

 due to the careful and repeated revisions of 

 the work by Sir John himself, and also to 

 the fact that many lists of nebulae existed 

 with which Sir John's catalogue was con- 

 stantly compared. No adequate idea of the 

 amount of labor expended upon the prepa- 

 ration of this list can be given here, but a 

 reference to the Introduction of that Cata- 

 logue must be made, where a concise ac- 

 count of the various revisions, collations, 

 and comparisons, with the reductions exe- 

 cuted (always in duplicate), extends over 

 five quarto pages. 



As the complete results of the observa- 

 tions of nebula: were now accessible to as- 

 tronomers in a convenient form, Sir John 

 Herschel turned his attention to the forma- 

 tion of an equally complete catalogue of 

 double stars. He proceeded assiduously 

 with this work, and at the time of his death 

 he had gathered data relating to over 10,000 

 stars, and had arranged these stars in order 

 of right ascension, and had foimed a synop- 



tical history of all the known observations 

 of about 4,000 of these. 



This " Catalogue," in its imperfect state, 

 was bequeathed to the Royal Astronomical 

 Society, and volume xl. of their "Memoirs" 

 contains the work completed in the form* 

 they have decided to give it, and for which 

 the Society, jointly with the editors (who 

 were but their agents), is responsible. So 

 far we have given a sketch of the history 

 of these two " Catalogues," gathered mainly 

 from the respective Introductions. We pro- 

 pose briefly to indicate the shortcomings of 

 the double-star catalogue, and we can do 

 this best by comparing it with its predeces- 

 sor in which Sir John Herschel's own plans 

 were fully carried out by himself, and which 

 naturally should have served as a model for 

 the execution of the later catalogue. We 

 will extract an entry from each of the two 

 catalogues, and will explain these, so that 

 an idea may be formed of the amount of 

 information which can be had about any 

 object contained in the two lists. The Ibl- 

 lowing extracts are made quite at random ; 

 the first from the " Catalogue of Xebuhe," 

 the second irom the " Catalogue of Double 

 Stars : " 



No. 2052; 688; 1,168; ; lO*- 9 49.9 ; 



+ 3.623; 1; 4'7"53'1".9; -f- 17".63 ; 

 1; pB; vL; R; vgbM; 4. 



No. 2052 ; h 698 ; ; 5'> 13' 48 ; 89 6' ; 



+ 3^09; 4".02. 



The first entry relates to No. 2052 of the 

 catalogued nebuhe, and we learn from it 

 (taking the numbers in their order from left 

 to right) that this nebula is No. 688 of Sir 

 John Herschel's previous catalogue ; is No. 

 168 of Sir William Herschel's Class I. ; that 

 no other persons have published any obser- 

 vations of this up to 1863 ; that its Right 

 Ascension for 1860.0 is 10'>949^9; that 

 the annual precession in Right Ascension 

 for 1880 is + 3^623; that the number of 

 observations upon which tliis place depends 

 is 1 ; that its North Polar Distance for 

 1860.0 is 47 53' 1".9 ; that the precession in 

 North Polar Distance for 1880 is+17".83; 

 that 1 observation was used to determine 

 its position in North Polar Distance ; and 

 that this Nebula is "/jretty i?right ; yery 

 iarge; ivound ; a'ery ^/radually 6righter in 

 the 1/iddle; and finally, that it has been 



