NATURE 



193 



THURSDAY, DECEMBER 29, 1892. 



GORE'S " VISIBLE UNIVERSE." 



The Visible Universe. By J. EUard Gore, F.R.A.S. 

 (London : Crosby Lockwood and Son, 1893 ) 



''"pH E object of this book is " not to propound any new 

 J- hypothesis, but simply to explain and discuss 

 theories which have been supported by well-known 

 astronomers and other men of science " as to the "evolu- 

 tion of the Solar System," and to give a popular account 

 of the " construction of the Universe as we see it, and its 

 probable development from pre-existent matter." 



Mr. Gore has already acquired considerable success as 

 a popular writer on astronomical subjects, and the scheme 

 of the present volume is, as we might expect, a very good 

 one. The first three chapters are devoted to a popular 

 account of the hypotheses of Kant and Laplace, the 

 principal objections that have been urged against them, 

 and the modifications and additions suggested by recent 

 research. In subsequent chapters such subjects as the fuel 

 of the sun, the luminiferous ether, the constitution of matter, 

 celestial chemistry, and the meteoritic hypothesis are 

 dealt with. Mr. Gore then reaches the purely descriptive 

 portion of his subject, and gives excellent chapters on the 

 Milky Way, and on " the latest results respecting the dis- 

 tribution of stars and nebulae and their relative motions." 

 Various theories of the construction of the Universe are 

 then discussed, and in a final chapter the idea of infinite 

 space and a finite universe is developed. 



Ahhough the general scheme of the book is excellent, 

 the execution falls in many places far short of its promise 

 and our expectations. When Mr. G )re confines himself 

 to the historical and descriptive his work is, on the whole, 

 well done, but in discussing theories he has in several 

 cases obviously ventured out of his depth, and has con- 

 sequently spoiled what would otherwise have been a 

 valuable addition to popular astronomical literature. 



For his chapters on the Nebular Hypothesis and Faye's 

 theory of the formation of the solar system Mr. Gore has 

 largely availed himself of M. Wolf's " Les Hypotheses 

 Cosinogoniques." He has also introduced extensive 

 quotations from " the late Mr. Jacob Ennis," but in con- 

 sidering Ennis as an authority, Mr. Gore is probably 

 alone. Mr. Ennis was, on his own admission, not a 

 mathematician, and certainly did not by " his own dis- 

 coveries," place the nebular hypothesis on a firm mathe- 

 matical basis. He proved Mars could not have satellites ; 

 that the heat of the sun was entirely due to chemical 

 combindtion ; that Sirius has twelve planetary attend mis ; 

 and made several other equally important discoveries. 

 His muhematical demonstration of the truth of the 

 nebular hypothesis is about as sound as the well-known 

 proofs th it the earth's surface is flat. Mr. Gore would 

 have done well to h ive omitted the quotations from Ennis, 

 and to have filled the space with a fuller account of the 

 recent mathematical investigations of the nebular 

 hypothesis, especially those of Prof. G. H. D irwin. 



Q loiing freely from Young and Sir William Thomson, 

 Mr. Gore is fairly safe in his chapter on the fuel of the 

 ^un, but he is in error in stating that " the 

 NO. 1209. VOL. 47] 



meteoric theory of the sun's heat must be abandoned." 

 It is true that the larger portion of the solar heat is 

 believed to be due t6 shrinkage, but it is generally con- 

 ceded that a considerable fraction has its origin in falls 

 of meteoric matter into the sun. .A. glaring case of the 

 misuse of a scientific term occurs in this chapter (p. 52), 

 whtre Mr. Gore is responsible for the statement that 

 "the theory generally held by astronomers ascribes the 

 heat of the sun to shrinkage of its mass caused by gravi- 

 tation." Mr. Gore surely meant volume. 



The chapter on celestial chemistry is meagre and un- 

 satisfactory. It seems incredible that the application of 

 photography to spectroscopic work is not even mentioned, 

 and that no allusion is made to the Draper catalogue of 

 photographic stellar spectra, to Rowland's photographic 

 mip of the solar spectrum, or to any of the recent photo- 

 graphic work. Mr. Gore is also in error in this chapter 

 when he states (p. 79) that although the great nebula in 

 Andromeda " has never been resolved into stars the evi- 

 dence of the spectroscope shows it is not gaseous." Bright 

 bands have been seen in the spectrum by Backhouse 

 Fowler, and myself, and these have been identified as 

 probably due to carbon radiation. 



The Meteoritic Hypothesis is dealt with in consider- 

 able detail, and here Mr. Gore is most seriously in error. 

 He gives what is professedly " a review of the principal 

 facts and arguments advanced by Lockyer," and care- 

 fully enumerates all the objections that have been urged 

 by " his opponents," ending the account with the opinion 

 that " on the whole, therefore, we seem bound to conclude 

 that the weight of evidence is against the truth of the 

 Meteoritic Hypothesis." The chapter bears internal evi- 

 dence that Mr. Gore began his consideration of this 

 hypothesis with thj opinion which he eiiunciates as his 

 final judgment, already formed. 



The summary of Prof. Lockyer's book has not been 

 made with the care that should have been bestowed upon 

 it. Tnere are at least two misquotations; on p. 91, 

 the substitution of " periastron " for " perihelion " makes 

 nonsense of what is otherwise an important paragraph, 

 and on p. 113 the omission of the word "other" con- 

 siderably modifies the meaning of the passage quoted. 



There are several errors due to hasty compilation, 

 observations and theories being attributed to Prof. 

 Lockyer in cases where he only quotes the observations 

 and adopts the theories. On p. 92 Mr Gore says " he 

 (Lockyer) also finds line absorption in Comet Wells 

 and the great September comet of 1883." This is mis- 

 leading, the observations of absorption having been made 

 by Copeland, Maunder, and Vogel. On p. 93 we find 

 the "theory that the light of comets is due to collisions 

 between the component meteorites" attributed to Prof. 

 Lockyer. The theory is due to Reichenbach, Tait, and 

 Sir William Thomson ; Prof. Lockyer's contribution being 

 the demonstration that spectroscopic observations lead 

 to and sUr)port the hypothesis. The results of Tail's cal- 

 culations given on pp. 227-229 of the " Meteoritic Hypo- 

 thesis " are also attributed to Lockyer on p. 93 of Mr. 

 Gore's book. On p. 95 we read, " the spectra of the true 

 nebulae consist of a very faint continuous spectrum 

 crossed by t)ne, two, three, or four bright lines " Lockyer 

 gives seventeen bright lines in his table. Mr. Gore's foot- 

 note that " the complete hydrogen series of lines were 



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