Miscellaneous Intelligence. 



26. TANNING OF LEATHER BY GRAPE MARC. 



A medical man of the neighbourhood of Narbonne has announced 

 that the marc of grapes, after being distilled for the purpose of 

 separating the alcohol, is an important assistant to oak bark, in the 

 tanning process. After preparing skins in the usual manner, he 

 placed them in the pits with the marc, in the place of bark. In 

 thirty-five or forty days the tanning was finished. The expected 

 advantages are, i. shorter time ; ii. reduction of the price of oak 

 bark : iii. a more agreeable odour of the leather than that given by 

 oak bark ; iv. greater strength in the leather *. 



27. ANALYSIS OF A SALIVARY CONCRETION, BY PROFESSOR GOEBEL, 



OF DORPAT. 



The calculus in question was one inch and a half in length, and 

 twenty-eight grains in weight, and consisted of a great number of 

 concentric layers ; it was examined in the following manner. The 

 digestion of fifteen grains of the powdered substance with sulphuric 

 ether yielded a colourless extract, by the evaporation of which one- 

 eighth of a grain of yellowish white fatty matter was obtained, which 

 had no taste or smell, was insoluble in water and alcohol, and on 

 being incinerated exhibited a slight trace of iron. The residuum of 

 the powder from the digestion with ether was boiled with alcohol, 

 the liquid evaporated, and half a grain of a yellowish substance 

 obtained, half of which was soluble in water; the solution was of 

 a weak saline taste, and had the odour of osmazome ; it was pre- 

 cipitated by the oxalate of ammonia and nitrate of silver. The 

 other half, which was not plissolved by the water, was soluble in 

 ether, and exhibited all the properties of the ethereal extract. The 

 remainder of the powder being boiled with water, a colourless solu- 

 tion was obtained, which, during evaporation, became of a red 

 colour, and yielded one grain and a half of a dry brownish residuum, 

 which was perfectly soluble in water, but not soluble in, nor dis- 

 coloured by, ether or alcohol. The red colour of the solution, which 

 very much resembled that of the sulpho-cyanate of iron, was entirely 

 destroyed by adding a few drops of liquid ammonia or muriatic acid; 

 and as the incinerated mass of the brown residuum, after having 

 been heated with a few drops of nitro-muriatic acid, and dissolved 

 in water, was precipitated by the tincture of galls, of a bluish black, 

 by the ferro-cyanate of potash, of a blue, and by the sulpho-cyanate 

 of potash, of the original red colour, there can scarcely be any doubt 

 that it proceeded from the presence of sulpho-cyanate of iron. In 

 order to ascertain this still more clearly, nine grains of the sub- 

 stance were boiled with distilled water, and on adding a few drops 

 of the solution of chloride of iron, the liquid was found immediately 

 to become of an intense red colour. No trace of potash could be, 



* Recueil Ipdustrielle, xvi. 85. 



