484 



NA TURE 



[March 23, 1905 



volume, while the value of accurate photographs of 

 animals as a means of instruction in natural history 

 is noticed in the concluding- paragraphs of the intro- 

 duction. 



Possibly, and if so pardonably, the author is in- 

 clined to over-rate the importance of photographic 

 illustrations in zoological work. In many respects, 

 such as representing birds in their natural surround- 

 ings, its importance cannot, indeed, be over-estimated. 

 But when the author goes on to deride the work of 

 the pencil of the artist as a means of illustrating 

 books on natural history, and to declare that the 

 wood-cut and the " process-block " are things of the 

 jjast in this connection, we take leave to differ from 

 such a sweeping assertion. Nor are we alone in so 

 doing, for Mr. VV. T. Hornaday, in his recently 

 issued " American Natural History," takes occasion 

 to point out that photography has its limitations in 

 the portrayal of animals, and that some illustrations 

 demand the artist's pencil in order to become satis- 

 factory zoological portraits. It is quite true, as Mr. 

 Brownell urges, that the sketch, as compared with 

 the photograph, may be crude and unfaithful to 

 nature, yet it will nevertheless often accentuate or 

 display essential features which are scarcely per- 

 ceptible or absolutely hidden in the sun-portrait. 



With this reservation, we are absolutely at one 

 with the author in regard to the extreme importance 

 and value of photography in natural history work, 

 and, like him, we look forward to the time when 

 real colour-photography will have been discovered 

 and made available for everyday use. After de- 

 scribing in full detail the general technique of the 

 photographic art and the kinds of camera and other 

 apparatus best suited to the outdoor photographer 

 of animal life, the author proceeds to discuss the 

 mode of procedure in the case of different subjects, 

 devoting one chapter to the larger mammals, another 

 to the small mammals, a third to birds, and so on. 

 So far as we can judge, all his advice is to the point, 

 and the illustrations given as samples are in most 

 cases admirable animal portraits. Not that attention 

 is confined to animated nature, for we have a chapter 

 on plant-photography, and another on the use of the 

 camera in depicting sporting scenes and incidents, 

 each as charmingly illustrated as their predecessors. 

 .Above all, the book is by no means dry reading, the 

 technical details being enlivened with numerous and 

 appropriate anecdotes. Mr. Brownell has, in fact, 

 succeeded in producing a treatise on practical field- 

 photography which it will be very hard to beat. 



R. L. 



A POPULAR STAR ATLAS. 

 Popular Star Maps. A Rapid and Easy Method of 

 Finding the Principal Stars. By Comte de Miremont, 

 F.R.A.S. (London: George Philip and Son, Ltd., 

 1904.) Price los. 6d. net. 

 T T is by no means an easy task to construct a 

 J- series of charts of the principal stars in the sky 

 that will at once be of service to those wishing to 

 NO. 1847, VOL. 71] 



make themselves familiar w ith the chief constellations 

 or star groupings. Many, if not the majority, of 

 star atlases printed for beginners are so belaboured 

 with lines indicating right ascensions and declina- 

 tions, names of constellations, Greek letters or 

 numbers against each star, different notations for 

 variable stars, &c. , that when the beginner turns his 

 eyes from the starry heavens towards a chart in 

 order to find out the particular grouping in question 

 he is unable to recognise it among the innumerable 

 markings. For this reason many who have made 

 valiant attempts to learn the stars have given up 

 trying, and it is the atlases that are to blame and 

 not the seekers after knowledge. 



The ideal set of charts for a beginner should in the 

 first place represent the appearance of the starry 

 heavens as near as possible, and consist of maps show- 

 ing small white discs or stars on a dark background, 

 the discs or stars varying in size according to the 

 inagnitude of the star ; secondly, a fairly large region 

 should be included in each map ; thirdly, only stars to 

 the third or fourth magnitude should be inserted ; and 

 lastly, each map should have an accompanying 

 duplicate chart or key-map on the same scale, but with 

 dark discs or stars on a white background, on which 

 as much information as may be useful should be given. 



In this way the beginner can at once find his par- 

 ticular stars on the first map, and learn their names, 

 &c., on the accompanying key-map. This seems to 

 be the logical method of aiding those who are not 

 accustomed to deal with star charts, and it is a 

 pleasure to find that such a series of maps is now 

 available for those who wish to take advantage of 

 them. 



The charts is question, ten in numb:-r, and each 

 accompanied by a key-map, have been prepared by 

 Comte de Miremont, one who is thoroughly 

 acquainted with the stars from the navigating point 

 of view, and is familiar with the desire of sailors and 

 others for a simple star atlas. Stars to the fourth 

 magnitude only are inserted, and these are repre- 

 sented, on charts lo inches square, as white stars 

 on a dark blue background ; in the accompanying 

 but separate key-maps, of the same size, the stars are 

 black on a white background. Great care has been 

 taken to ensure accuracy in the star positions. 



The method of projection, namely, the gnomonic, 

 is also one which lends itself well to this type of 

 atlas, for the whole of the celestial sphere can be 

 projected on six plates, each plate thus representing 

 one side of a cube enveloping the sphere. The upper 

 and lower sides of the cube enclose the north and 

 south polar regions respectively, and the other four 

 sides the equatorial regions. To render more 

 clearly the relations to each other of star groups near 

 the edges of each of these equatorial sides in contact, 

 four additional overlapping maps are added. Thus 

 there are ten charts in all, and there is this advantage, 

 that each one with its corresponding key-map can be 

 taken out of the portfolio and used in the observatory, 

 in the field, or on board ship by itself. On each chart 

 and its key is a scale of right ascensions with the 

 seasons of the year when each of the constellations is 



