142 Notices resjiecthig New Books. 



pendently of the Association in 1870, is a fourth area of the map? 

 in continuation of the original plan, and which occupies the first 

 place in the present volume. Pacing page 1 we have an excellent 

 map of the area, carefully drawn in outline, accompanied by a full 

 descriptive catalogue of 99 craters and other objects situated upon 

 the area. The description is completed by a comparison of four pho- 

 tograms. The numerous notes and woodcuts of interesting objects 

 must be highly suggestive to every earnest student. 



The very complete monograph of the Mare Serenitatis is of itself 

 a work capable of sustaining the reputation of the author of the 

 four areas, comprising as it does so large a descriptive catalogue of 

 objects within this large and perhaps best-known of all lunar plains, 

 supplemented by copious notes, and illustrated by a map completely 

 crowded with objects, some of them very small indeed. As far as 

 we are able to judge, it is quite a model production. It also con- 

 tains a very interesting examination of Schroter's drawings of the 

 region, and a comparison of them with recent photograms and the 

 present appearance of the plain. 



Hipparchus is the subject of another masterly monograph, illus- 

 trated by a well-engraved map, accompanied by a full catalogue of 

 objects and numerous descriptive notes, together with a comparison 

 of the region on different photograms. The scale of the map is 

 100 inches to the moon's diameter. We notice that the paging of 

 the letterpress of Hipparclius runs on from that of the Mare tiere- 

 nilatis, from which we suppose other monographs are to follow. 

 Certainly every lunar observer must hope that may be the case ; 

 indeed the continuance of the areas of the map is a very desirable 

 thing while we have nothing at all of the kind which depicts one 

 hundredth of the lunar features revealed by the average telescope 

 now in the hands of amateurs. Beer and Madler's map was a 

 worthy work in 1837 ; but nearly forty years have brought about 

 great improvements in instruments for the purpose of observa- 

 tion, and, as it seems to us, a map which would bring seleno- 

 graphy more nearly level with the times is really an important 

 desideratum. 



Following the three maps to which we have referred, we have 

 specimens of the Catalogue of Lunar Objects according to the plan 

 originally devised by Mr. Birt. This catalogue certainly has the 

 merit of clearness and conciseness ; and, by means of a most useful 

 accompanying table of references and synonyms, the student is able 

 easily to compare the notes of different observers and authors on 

 each particular locality which may be under discussion. This is a 

 valuable adjunct to the descriptive notes and illustrations. What 

 our star-catalogues are to stellar observers, that would Mr. Birt's 

 projected work be to students of the moon, if it were only carried 

 out to completion. The method of arrangement adopted through- 

 out all Mr. Birt's productions seems to be a specialite of his own. 

 Other works on the moon we could name, written in what is called 

 the popular style, and illustrated by excellent pictorial representa- 

 tions of the general character of the lunar surface : but from all 



