114 MR. EDWARD SCHUNCK ON SOME 



evaporating the solution as a dark -brown, shining, brittle, 

 amorphous resin, which is transparent in thin layers. In 

 boiling water it softens and melts to a pasty mass, which 

 becomes hard and brittle again on cooling. It is insoluble 

 in ether, and is accordingly precipitated on the addition of 

 ether to the alcoholic solution. When heated on platinum 

 it melts, swells up considerably, and burns with a bright, 

 but smokeless, flame, leaving a very voluminous coal which 

 gradually burns away, only a slight trace of ash being left. 

 It contains nitrogen, and when heated with soda-lime gives 

 off ammonia in abundance. It dissolves in concentrated 

 sulphuric acid and in glacial acetic acid, giving dark- 

 brown solutions, from which it is reprecipitated by water 

 in brown flocks. It is easily decomposed by boiling nitric 

 acid, yielding a yellow solution, which on evaporation 

 leaves an abundance of oxalic acid, but no picric acid. It 

 is easily soluble in caustic and carbonated alkalies, giving 

 dark yellowish-brown solutions, from which it is repreci- 

 pitated by acids in light-brown flocks. The ammoniacal 

 solution leaves, on evaporation, a dark-brown, amorphous 

 residue, which does not dissolve again entirely in water, in 

 consequence of a loss of a part of its ammonia during eva- 

 poration. The ammoniacal solution gives brown precipi- 

 tates with the; chlorides of barium and calcium, but none 

 with sulphate of magnesia. With nitrate of silver it yields 

 a dark reddish-brown precipitate, which dissolves com- 

 pletely in an excess of ammonia, giving a yellowish-brown 

 solution, which remains unchanged on being boiled. The 

 alcoholic solution of the substance gives brown precipitates 

 with the acetates of baryta, lead, and copper. On the ad- 

 dition of an alcoholic solution of potash it gives a brown 

 precipitate, which sinks rapidly, forming a glutinous deposit. 

 A similar efi'ect takes place when an alcoholic solution of 

 soda is employed. The substance is easily soluble in a 

 boiling solution of acetate of soda, and is reprecipitated by 



