IV CONTENTS OF VOL. XV. — FOUKTH SERIES. 



Page 

 Prof. Clausius on the Conduction of Electricity in Electrolytes. 94 

 Dr. Atkinson's Chemical Notices from Foreign Journals .... 109 

 Dr. Schunck on the Formation of Indigo-blue. — Part II. (co/i- 



tinued) 117 



Dr. Heddle on some new Forms of British Sphenes 134 



Mr. G. J. Stoney on the Adjustments uf the Needle of a Tan- 

 gent-galvanometer 1^5 



Notices respecting New Books : — Mr. R. Galloway's Manual 



of Qualitative Analysis 140 



Proceedings of the Royal Society : — 



Dr. Hofmann on the History of Thialdine 140 



Dr. Hofmann on the Action of Sulphuric Acid upon Anisic 



and Salicylic Acids • . . . . 143 



Mr. F. Field on the Separation of Iodine, Bromine, and 



Chlorine 144 



Profs. Andrews and Tait on the Density of Ozone 146 



Dr. Hofmann on the History of the Phosphorus-, Arsenic-, 



and Antimony-bases 147 



Dr. Franklaud on a New Series of Compounds derived 



from Ammonia and its Analogues 149 



Proceedings of the Geological Society : — 



Mr. H. C. Sorbyonsome peculiarities in the Microscopical 



Structure of Crystals 152 



Mr. J. Prestwich on the Boring through the Chalk at Har- 

 wich 154 



Mr. U. Godwin- Austen on a Granitic Boulder out of the 

 Chalk of Croydon, and on the Extraneous Rock-frag- 

 ments found in the Chalk 155 



On the Telestereoscope, liy Walter Hardie 156 



On the Relations existing between certain Groups of Crystalline 



forms belonging to different Systems, by C, Marignac .... 157 

 On the Composition of Epidotes, Vesuvians and Garnets, by R. 

 Hermann 159 



NUMBER XCIX.— MARCH. 



M. Poinsot on the Percussion of Bodies 161 



Mr. A. Gages on Pseudomorphic Tremolite encrusted with Car- 

 bonate of Lime and Magnesia, being apparently the mineral 

 described by Dufrenoy under the name of Miascite 180 



Dr. Schunck on the Formation of Indigo-blue. — Part II. (co7t- 

 cluded) 1 83 



Dr. Lloyd on the direct Magnetic Influence of a distant Lumi- 

 nary upon the Diurnal Variations of the Magnetic Force at 

 the Earth'a Surface 192 



Dr. Debus on the Action of Nitric Acid on Glycerine. — First 

 Memoir 196 



