244 



NATURE 



[January ii, 1894 



point out that Prof. Rowland first made the striking re- 

 mark that " were the whole earth heated to the tempera- 

 ture of the sun, its spectrum would probably resemble 

 that of the sun very closely " {Johns Hopkins University 

 Circular, No. 85, February, 1891). In referring to Prof. 

 Rowland's work in August, 1891, at the British Associa- 

 tion meeting of that year. Dr. Huggins made practically 

 the same remark, and Sir Robert Ball (p. 169) quotes 

 his words, and gives him the credit for the idea they 

 contain. 



r-.vo of the chapters in the book refer to shooting- 

 stars, meteors, and meteorites ; and in them the authoj- 

 discusses the origin of meteorites and the relation be- 

 tween meteorites and comets. In his opinion, meteorites 

 are masses of matter ejected from terrestrial volcanoes 

 in a primeval condition of the earth ; but we fancy that 

 the analyses of most meteorites do not favour this origin. 

 How, for instance, is the absence of quartz accounted 

 for? But, as a matter of fact. Sir Robert Ball is almost 

 the only astronomer who holds the volcanic view, and 

 the same can be said with regard to his denial of the con- 

 nection between comets and meteorites, and between 

 meteorites and shooting-stars. The work of Schiaparelli 

 and Newton, Tisserand, and Schulhoff, not to mention 

 many others, considerably outweighs all that Sir Robert 

 Ball has ever said upon the matter. The spectroscopic evi- 

 dence upon the connection is dismissed in half a dozen 

 lines, while page upon page is devoted to a description 

 of what might happen to masses of matter projected 

 from the moon or a minor planet. In fact, by discussing 

 and judging these theories in a volume designed for the 

 general reader, Sir Robert Ball has made a mistake. 

 Though he has done some excellent mathematical work, 

 astronomers are not at all ready to recognise him as a 

 judge on matters of astronomical physics. His function 

 is to expound and popularise discoveries in celestial 

 science, and when he is exercising it he is at his best. 



There are some good points about the book, and any- 

 one desirous of obtaining information upon a few of the 

 recent important discoveries in astronomy will profit by 

 reading it. The illustrations are not so numerous as 

 they ought to be, but what are included are mostly very 

 good, though the illustration on p. 156, of the region of 

 the Milky Way about /3 Cygni, should have been a posi- 

 tive instead of a negative, for in its present form it looks 

 more like a pathological section than anything else. 



It would be an advantage if, in a future edition, the 

 author would give the name of the observer of the solar 

 eruptions figured on pp. 271, 273, 338, and 339. We 

 fancy that Father Fenyi was the original draughtsman of 

 the prominence forms there illustrated, but cannot find 

 his name mentioned in the text relating to them. 



R. A. Gregory. 



OUR BOOK SHELF. 



Practical Agricultural Chemistry for Elementary 

 Students. By J. Bernard Coleman, A.R.C.Sc, F.I.C., 

 and Frank T. Addyman, B.Sc, F.I.C. (London : 

 Longmans, Green, and Co., 1893.) 



" The course of instruction described in this book has 

 been in use for some years at University College. \ 

 Nottingham." After a few instructions as to the use of 

 apparatus, there follows a short course of experiments on 



NO. 1263, VOL. 49] 



oxygen, air, carbonic acid, water, and hydrogen. The 

 third section treats experimentally of soils, manures, feed- 

 ing materials, and dairy produce, and gives a number of 

 simple experiments that serve to show many of the most 

 important properties of these substances. For example, 

 the differences between the sulphur present in gas-lime 

 and in gypsum respectively, and the various conditions in 

 which phosphoric acid occurs in superphosphates, bone 

 phosphates, reverted phosphate, and slag phosphates are 

 made the subjects of experiment, Tests are given for the 

 various constituents of manures. Oilcakes, grass and 

 hay, roots, flour, milk, butter and cheese, are dealt with 

 in a similar manner. The fourth section of the volume 

 gives a few reactions of a select number of metals (viz. 

 seven) and acids, with a few other matters, and tables 

 for the qualitative analysis of substances containing them. 

 We would remark in reference to this, that to allow 

 students to fuse insoluble substances in porcelain crucibles, 

 in order to test for silica, is, to say the least of it, un- 

 desirable. 



Regarding the volume as a whole, it forms an excellent 

 addition to an ordinary student's course of agriculture, 

 whether this is, as is too often the case, only a matter of 

 listening to a few lectures, or whether practical agri- 

 culture forms an essential part of it. Perhaps it is hardly 

 possible for a teacher to take much account of the danger 

 that is proverbially inseparable from a little knowledge ; 

 but in cases where this is particularly liable to manifest 

 itself, it may be his duty to do what he can to obviate the 

 evil. Speaking from e.xperience, we fear there are students 

 who, after having worked through these seventy-one 

 pages, would not hesitate to state that they had studied 

 inorganic and organic practical chemistry at whatever 

 college they might have done the work. In this way it is 

 at least possible for grave discredit to be brought un- 

 deservedly upon the usual course in chemistry at such a 

 college ; for there are many people with no technical 

 knowledge of these matters, who attach considerable value 

 to the mere fact that a specific routine of study has been 

 gone through at a well-known educational establishment. 

 It appears, therefore, to be highly desirable to do what- 

 ever may be possible to prevent such a chemical course 

 as that in this volume from being in any way confused 

 with even the most elementary course that is arranged to 

 impart a knowledge of chemistry itself. A similar danger 

 doubtless exists in many other cases, but it may probably 

 be said with truth, that there is in none other likely to be so 

 great a temptation to misrepresent facts by an incomplete 

 statement of the truth. C. J. 



Bionomie des Meeres. Von Johannes Walther. Erster 

 Theil einer Einleitung in die Geologie als historische 

 Wissenschaft. (Jena : Gustav Fischer, 1893.) 



Prof. Walther has set before himself an ambitious 

 programme, which, if carried out, should result in a geo- 

 logical treatise of great interest ; we fear also of porten- 

 tous length. The first instalment is a modest little book 

 of 200 pages, with a preface summarising the travels and 

 researches which the author made for ten years with a 

 view to fit himself for the task, and a separately paged 

 introduction defining the scope of the contemplated work, 

 and enunciating the ontological method in geology. 

 Bionomy is the study of the life-habits of organisms in 

 relation to their environment, and it is obvious that the 

 bionomy of the ocean at the present time must be the 

 clue to all deductions from the character of marine fossils 

 regarding the physical conditions in which they were 

 produced. 



Prof. Walther is extremely systematic, and in twenty 

 numbered sections he summarises a vast amount of recent 

 work on the relation between marine organisms and 

 physical conditions. His numerous references to original 

 memoirs might be profitably increased by the inclusion 

 of more British, French, and American work, and espe- 



