270 



SCIENCE. 



IN. S. Vol. XVI. No. 398. 



while he is at the same time performing la- 

 borious investigations, editing the Zeitschrift 

 fur Physikalische Chemie, and doing the large 

 amount of teaching that falls to his lot. 



The work under consideration appeared in 

 Germany about two years ago, and the recent 

 appearance of a good translation of it is to be 

 heartily welcomed, for in many respects this 

 is a noteworthy and useful book. The English 

 edition does credit to the publishers in being 

 a handsome book, which, as it happens, is more 

 attractive than the German one. 



We have here an attempt to introduce a 

 good deal of physical chemistry into the teach- 

 ing of elementary inorganic chemistry. While 

 this aim is a praiseworthy one, to some extent 

 at least it appears to the reviewer that Profess- 

 or Ostwald has gone somewhat too far in this 

 direction. The book seems to be too difficult 

 for any but mature and highly talented begin- 

 ners. However, for chemical students of con- 

 siderable experience, and in fact for a very 

 large number of chemical readers the work 

 will undoubtedly be valuable, for it contains 

 clear and simple explanations of the points 

 of physics that every educated chemist should 

 know. Many physical matters are treated in 

 a very interesting and suggestive way. 



So much has been said in praise of the book 

 that a few adverse criticisms may be allowed. 

 In the first place, one important reason why 

 the work would be diificult for a beginner is 

 the fact that the author, while admitting that 

 the atomic hypothesis is of great value for the 

 purposes of instruction and investigation, 

 avoids the use of this and of the molecular hy- 

 pothesis as far as ' the present usage of lan- 

 guage will permit.' His reason for so doing 

 is that these are hypotheses, not realities. If 

 he were consistent he would not use the ionic 

 hypothesis, but he employs the latter to the last 

 degree, and even occasionally alludes to ions 

 in solid substances. The question may well 

 be asked, can ions be assumed to exist without 

 the assumption that atoms and molecules 

 exist? The attitude of certain physicists in 

 abandoning the atomic and molecular theories 

 must appear absurd to chemists until some- 

 thing better is brought forward to replace 

 those theories, for, what could an organic 



chemist do, for example, if he gave up atoms 

 and molecules ? 



Another fault of the b.ook is the occurrence 

 of too many inaccurate statements. The 

 translator says that the mistakes that had 

 crept into the German edition have been, as 

 far as possible, corrected; but still many re- 

 main that have been noticed, and it may be in- 

 ferred that there are others which the reviewer 

 was not wise or diligent enough to detect. A 

 few examples will sufiice to show the character 

 of the errors. 



The statements in regard to the amounts of 

 carbon in iron and steel are contradictory and 

 incorrect (pp. 563, 564, 585). The erroneous 

 statement is made that sulphur can be readily 

 removed with carbon and silicon in the ordi- 

 nary Bessemer process (p. 585). Talc, which 

 contains water, is given as an example of an 

 anhydrous silicate of magnesium (p. 537). It 

 is stated that the most frequent types of the 

 double salts of antimony trichloride and tri- 

 iodide are M^SbCl, and MSbl, (p. 700), 

 whereas these are rather rare types in both 

 cases. Lead tetracetate, which is white, is 

 called yellow (p. 652). 



The translator's work has been very well 

 done. One typographical error, which is not 

 copied from the original, is noticed (p. 463) 

 where 42,400 c.c. instead of 22,400 c.c. are giv- 

 en, which makes the volume of gas produced 

 by the explosion of gunpowder altogether too 

 large. In the table showing the periodic ar- 

 rangement of the elements the translator has 

 corrected the atomic weights of krypton and 

 xenon, according to recent determinations, 

 from 45 and 65 to 82 and 128, but, curiously 

 enough, he has left the new numbers in the 

 old places instead of putting them in the 

 places called for by their magnitudes. The 

 translator has introduced some curious names 

 for ions, such as potassion, lithion, triferrion, 

 carbanion, sulphanion, etc. As long as these 

 are self-explanatory there can be no serious 

 objection to them, but without having master- 

 ed the nomenclature one might be in doubt 

 whether the last, ' sulphanion,' referred to the 

 sulphide, sulphite or sulphate ion. 



H. L. Wells. 



