15 



With silver nitrate it forms a fine black precipitate moderate- 

 ly soluble in alcohol, which, on boiling is reduced with the for- 

 mation of a metallic mirror. Platinum chloride, gold chloride, 

 uranium acetate, and copper nitrate form precipitates varying 

 in color from brown to black. 



He prepared the lead compound by precipitating with ace- 

 tate of lead, washing with alcohol and then with boiling water, 

 drying on a water bath and finally over sulphuric acid in an 

 exsiccator. He obtained by analysis the following results: 



THEORETICAL FOR 

 FOUND (CuH 17 O)jPb. 



C 52.08 52.4 



H 5-34 5-3 



O 10.43 10.01 



Pb 32-45 32.29 



The lead salt is gray ; on heating to 100 it gives off a pecu- 

 liar odor, turns dark, at iio-ii5 melts to a brown mass, and 

 at about 120 ignites spontaneously. 



By adding an insufficient quantity of ferric chloride he 

 formed a voluminous black precipitate, which by analysis gave 

 the following formula: (C 14 H 17 O 2 ) 3 Fe+9C 14 H 18 O 2 . 



By adding a larger proportion of ferric chloride he formed 

 a compound which on analysis gave results corresponding to the 

 following formula: (C 14 H 17 O 2 ) 3 Fe+3C, 4 H 18 O 2 . Both salts 

 melt to a black mass at io5-no and ignite spontaneously at 

 a somewhat higher temperature. 



Free alkalies impart a very dark color to the alcoholic sol- 

 ution, which looks purplish-black by transmitted light and dark 

 brown by reflected light. On exposure to air it forms a viscid 

 compound, rapidly becomes black and dries up. 



Soluble salts of mercury, zinc, nickel, cobalt, manganese and 

 earthy metals do not give any distinct reaction. 



To a solution of the acid in carbon disulphide, bromine was 

 gradually added in excess and the whole evaporated to dryness 

 on a water bath, the mass extracted with strong alcohol, and the 

 extract again evaporated, whereupon it yielded a dark semi-fluid 

 mass. This was examined for bromine by igniting with pure 

 lime. 0.7060 gm. gave 1.151 gm. AgBr= 69.37% f bromine 

 agreeing very nearly with a hexabromo derivative of the acid, 

 C 14 H 12 Br O 2 , which requires 69.36%. 



