Notices respecting New Boohs. 389 



from zincethyl ; water and dilute acids convert zincethyl into 

 a hydrate and methyl, &c. 



Some inorganic compounds of metals are known as very bad 

 conductors, e. g. stannic chloride (Sn Cl 4 ); I obtained no de- 

 flection with a battery of 80 Bunsen elements. This may be 

 in accordance with its chemical character, since stannic chlo- 

 ride is, in various reactions, almost always taken up as a group 

 of atoms without being decomposed. The same remark holds 

 good for the pentachloride of antimony and the chloride of 

 arsenic, with which I have found Buff's results * confirmed 

 Avith much more powerful currents. The combinations of the 

 halogens with mercury are fusible, and yet are very bad con- 

 ductors of electricity ; nevertheless they are decomposed by 

 most of the metals, and appear to be held together by only 

 feeble affinity. Hittorf sought to bring these facts into har- 

 mony with each other, by remarking that the decompositions 

 by double elective affinity are absent here, since the oxygen 

 acids, which are regarded as the most powerful, will not de- 

 compose these compounds either diluted or concentrated, 

 either cold or with the aid of heat. But this remark is not 

 applicable to the organo-metallic compounds, upon which 

 acids, whether concentrated or diluted, immediately act, and 

 furnish new bodies as the products of decomposition. Thus, 

 for example, zincethyl gives with hydrochloric acid chloride 

 of zinc and methyl ; mercuryethyl with diluted sulphuric acid 

 gives methyl and a compound of sulphuric acid and ethyl, &c. 

 Consequently it follows from this series of experiments that 

 no simple relation can here be demonstrated between chemical 

 decomposition and electrolysis. 



[To be continued.] 



LIV. Notices respecting New Books. 



Die Potential/unction und das Potential, ein Beitrag zur mathe- 



matischen PhysiJc von B/. Clatjsius, Dritte vermehrte Auflage. 



Leipzig, 1877. Verlag von Johann Ambrosius Barth. (Boyal 



8vo, pp. 178.) 

 pKOFESSOB CLATJSIUS states that the object of his treatise 

 ■*■ is to make the reader acquainted in the simplest possible manner 

 with the function to which Greer gave the name of the Potential 

 function. He does this by developing the subject very systema- 

 tically from first principles, dwelling with great exactness and 

 perfect clearness on every point that is likely to give the reader 



*^ Pogg. Ann. vol. ex. p. 267, 1859. Buff found no conduction in these 

 bodies with a battery of 16 elements, and holds that stannic chloride is an 

 absolute nonconductor. Lapschin and Tichanowitsch likewise observed no 

 conduction with the current of 370 elements in oxychloride of antimony. 



