April 13, 191 6] 



NATURE 



139 



poses of the fraud-theory. Some of this matter 

 may be due to thought-transference ("telepathy") 

 from hving- people ; but in some cases it seems 

 almost necessary to admit telepathy from the so- 

 called dead. Particularly is this the case in regard 

 to George Pelharn, whose evidence is given in an 

 earlier volume of "Proceedings" — No. 13. 



All investigators admit that the evidence in that 



volume is impressive, and that the Piper case as a 



whole is remarkable. It is still more remarkable, 



perhaps, to find so cautious a mind as Mrs. Sidg- 



' wick's accepting communication from the dead as 



■. a reasonable hypothesis, even though she does 



dignify it with the sounding title of telepathy 



through a personation or subliminal fraction. Cer- 



' tainly the evidence does seem beginning to appear 



i conclusive or almost so. It can no longer be 



j ^'vanquished with a grin." Perhaps in due time it 



may become so strong that man's survival of 



death will be a scientific as well as a religious 



: belief. Meanwhile, such volumes as that under 



; notice are very welcome as showing a "via media 



i between extremes of credulity and incredulity, 



Avhich are equally unscientific and regrettable. 



J. A. H. 



ANALYTICAL AIDS FOR FACTORY 



CHEMISTS. 



\Solvents, Oils, Gums, Waxes, and Allied Suh- 



1 stances. By F. S. Hyde. Pp. vi + 176. (Lon- 



'lon : Constable and Co., Ltd., 1915.) Price 



S5. 6d. net. 



j A T the moment the factory chemist is very 



i •^*- much before the public. The university- 



jtrained man complains of the ver>' inadequate 



reward which he can obtain for his labours. The 



juanufacturer is reported to be dissatisfied with 



i:he chemist fresh from the university, and all 



parties criticise the present methods of training. 



t might be at least expected that the technical 



chemist should know cherhistry, meaning thereby 



I full knowledge of the properties, preparation, 



md manipulation of the commoner substances, 



»oth inorganic and organic ; that he should under- 



tand the spirit of research and how to set about 



problem ; that he should be versed in getting 



p the literature. The fact is, such chemists are 



are; a real knowledge of chemistry, particularly 



rganic chemistry, is largely neglected. As a 



onsequence special text-books are provided for 



^e use of factory chemists, such as the one before 



It contains in the minimum number of words 



hort statement as to the properties of a variety 



organic substances, and will serve as a useful 



jijunct to the memory of the properly trained 



Ian. In the hands of others it is more likely to 



-^lead, since as a result of the condensation 



essary, the information is often scrappy and 



lequal, and the true spirit of organic chemistry 



missing. 



For example, the statement that dextrose is less 

 yeet than cane sugar, though true, in no way 

 nveys the proper idea to anvone imperfectly 

 quainted with the great difference between the | 

 NO. 2424, VOL. 97] 



two sugars in appearance and in crystalline char- 

 acter. Glucosides are defined as substances 

 which " on fermentation " or by hydrolysis yield 

 glucose. Ethyl alcohol is dismissed in nine lines ! 

 Ten pages suffice for the alkaloids and bitter prin- 

 ciples. 



As a whole, the book is well done ; it is full 

 of information, accurate and up-to-date, particu- 

 larly as regards the sections devoted to oils, fats, 

 and waxes, which occupy more than half the con- 

 tents. This branch of chemical analysis involves 

 the use of a number of special methods^ largely 

 empirical in character, and usually labelled with 

 the names of their proposers, with which the 

 would-be expert must be acquainted. For this 

 purpose he will find Mr. Hyde's book most 

 helpful. 



It will be much more to the advantage of the 

 individual worker as well as of the works labora- 

 tory, however, if information be sought from the 

 larger manuals of chemistry and the critical faculty 

 in analysis is cultivated, instead of striving more 

 or less mechanically to carry out operations as 

 quickly as possible, by following explicit instruc- 

 tions without any real understanding of the chem- 

 istry of the reactions concerned. 



ASTRONOMY FOR JUVENILE READERS. 



A Voyage in Space: A Course of Six Lectures 

 ''Adapted to a Juvenile Auditory" delivered at 

 the Royal Institution at Christmas, 1913. By 

 Prof. H. H. Turner. Pp. xvi + 304. (London: 

 S.P.C.K., 1915.) Price 65. net. 



THE voyage in space which forms the subject 

 of this book is not a romantic flight of the 

 imagination, such as might have been written by 

 Jules \'erne, but an account of a journey by tele- 

 scope. In other words, it is an elementary book 

 on astronomy, and is founded on a course of 

 lectures to young people at the Royal Institution. 

 Following the example of Faraday on a similar 

 occasion, the author has retained the language of 

 the lecture room, and has thus been able to pre- 

 serve the freshness of the original presentation. 

 The reader is necessarily deprived of witnessing 

 the actual experiments, and of seeing many of the 

 pictures exhibited by the lantern, but the descrip- 

 tions are so vivid and the illustrations so numer- 

 ous that he will readily imagine himself to be a 

 member of the audience. 



The difficulty of leaving the earth in the flesh 

 provides the occasion in the first lecture for an 

 account of gravity in its historical, experimental, 

 and astronomical aspects. Then, in the second 

 lecture, the immense distances which have to be 

 traversed before reaching the heavenly bodies are 

 dealt with, and an interesting talk is devoted to 

 our own atmosphere, which must necessarily be 

 passed through during the first part of the voyage. 

 Telescopes, as the only means of travelling to 

 distant spheres, are the subject of the third lec- 

 ture, and subsequent lectures deal respectively 

 with visits to the moon and planets, to the sun, 

 and to the stars. 



