MM. Millon and Commaille on the Reduction of Silver, 541 



The author has described the sulphate, the acid sulphate, and 

 the acid phosphate, all of which salts crystallize well. 



Lautemann has found* that, by the action of hydriodic acid, 

 kinic acid, C 14 H 12 12 , is reduced to benzoic acid, C 14 H 6 0*; 

 the action succeeds both by heating an aqueous solution of 

 hydriodic acid with kinic acid, and by heating an aqueous solu- 

 tion of kinic acid with iodide of phosphorus. In the latter case 

 the quantity of benzoic acid obtained is almost that required 

 theoretically. 



The author has also found that kinic acid is reduced to benzoic 

 acid when taken into the organism. 



According to Millon and Commaille f, when a solution of 

 ammoniacal subchloride of copper is added to a solution of 

 nitrate of silver, also containing ammonia, an instantaneous 

 precipitate of absolutely pure metallic silver is obtained. The 

 precipitated silver is amorphous, and in the very finest state of 

 division, while that obtained by electric currents or by metals 

 is always crystalline and generally lustrous. The amorphous 

 silver is of a light grey, but sometimes almost white ; under the 

 burnisher it takes the brightest metallic lustre, and in virtue of 

 its fine state of division it can be applied to the most varied 

 materials, such as wood, stone, leather, &c. 



By the weight of silver precipitated, the quantity of suboxide 

 of copper engaged in the reaction is at once determined ; the 

 presence of protosalt does not interfere with the reaction, which 

 thus gives at once an accurate method of analysing a mixture of 

 proto- and sub-salt of copper. 



The authors find that the chloride of silver in ammoniacal 

 solution is precipitated by this method, which is thus very well 

 suited for working up laboratory residues. They also suggest 

 its application on the large scale to the extraction of silver from 

 argentiferous minerals. 



Kolbe and Lautemann foundj that when sodium is dissolved 

 in phenylic alcohol, C 1 " 2 H 6 O 2 , in an atmosphere of carbonic acid, 

 salicylic acid, C 14 H G O 6 , is formed; and by similar treatment 

 the homologous cresylic alcohol, C 14 H 3 O 2 , and thymylic alcohol, 

 C 20 H 14 O 2 , are resolved into new acids, cresotic acid, C 16 H 8 6 , and 

 thymotic acid, C 22 H 14 G , which are homologous with salicylic 

 acid. Scheuch has investigated § in this direction the deport- 

 ment of eugenic acid, the main constituent of oil of cloves. This 



* Liebig's Annalen February 1863. 

 f Comptes Rendus, February 16, 1863. 

 X Phil. Mag. vol. xx. p. 384. 

 § Liebig's Annalen, January 1863. 



Phil Mag. S. 4. No. 171, Suppl. Vol. 25. 2 



