Chemistry and Physics. 79 



ored product is obtained when the ferrous and ferric atoms are 

 combined, not by cyanogen but by oxyaen, as in the long-known 

 Aethiops martialis, which is produced by adding an alkali to a 

 solution containing both ferrous and ferric salts. They mention 

 also surprisingly similar instances of colored compounds in "red 

 lead" which contains lead in the bivalent and quadriva- 

 lent conditions ; in the indigo-blue, S 2 3 , in which the sulphur is in 

 different states of oxidation ; in uranous-urannic oxide, tJ 3 8 , etc. 

 — Liebig's Ann. cccxlii, 364. h. l. w. 



5. Researches on the Affinities and on the Causes of the Chemi- 

 cal Similarity or Dissimilarity of Elements and Compounds ; by 

 Geoffrey Martin. 8vo, pp. 282. London 1905. (J. & A. Church- 

 ill.) — In dealing with this work the reviewer is warned to be 

 cautious, for the author says in his preface ; " My conclusions are 

 somewhat at variance with the current notions of chemists, and 

 this will, perhaps, lay me upon [open] to attack. My critics will 

 find, however, that they are dealing with a prepared opponen 

 who will mast[er] them on their own ground." This extract 

 gives some instances of the extraordinary number of mistakes in 

 printing that are to be found in the book, and these with a mul- 

 titude of mistakes in grammar and spelling interfere seriously 

 with reading the work. The author has taken the periodic sys- 

 tem of the elements and has made for each element what he calls 

 an affinity surface by erecting perpendiculars upon the plane of 

 the periodic system of such length that they represent the relative 

 affinities of the other elements for the elements in question, and 

 by passing a surface through the ends of the perpendiculars, pro- 

 ducing an irregular form. As far as we can see, these surfaces 

 lead to no new insight into the periodic law. Numerous conclu- 

 sions are reached, not all of which are novel, among which the 

 following may be mentioned : Chemically unstable compounds 

 are volatile and fusible; chemically stable compounds are fixed 

 and fusible with difficulty. Compounds of a high valency grade 

 are more volatile than compounds of a low valency grade. The 

 physical and chemical properties of an element depend upon the 

 forces with which it attracts other elementary kind of atoms. 

 Chemical similarity is invariably accompanied by physical simi- 

 larity. Volatility, fusibility, etc., depend on the attractive forces 

 the atoms exert, and not to any great extent upon their molecu- 

 lar weight. It seems to the reviewer that the author has shown 

 a decided tendency to fit facts to his theories, and to overlook 

 contradictory facts. h. w. f. 



6. Verflussigtes Ammoniak als Losunysmittel / von J. Bronn. 

 8vo, pp. 252. Berlin, 1905. (Verlag von Julius Springer.) — This 

 book gives a very full account of what is known about liquefied 

 ammonia, particularly as a solvent. The work will be of great 

 convenience to those who wish to obtain information on this sub- 

 ject, since such information has heretofore been scattered through 

 many journals in several languages. The book furnishes also a 

 convenient source of references to the literature. h. l. w. 



