126 Dr. J. Stenhouse on Amido-derivatives of Orcin. [Jan. 23, 



produced directly by adding hydrochloric acid to the blue solution of the 

 base in caustic soda obtained from trinitro-orcin by sodium-amalgam, it 

 forms long silky needles of a brownish-red colour : an aqueous solution 

 of the acetate or hydrochloride precipitated by an excess of hydrochloric 

 acid yields a mixture of these needles with rhomboidal plates ; the latter 

 are purple by reflected light, and of an olive-green colour by transmitted 

 light. The slow oxidation of the hydrochloric-acid solution of triamido- 

 orcin obtained by means of tin and hydrochloric acid yields dark-coloured 

 short thick prisms. The hydrochloride is insoluble in alcohol and ether, 

 moderately soluble in cold water, and readily in boiling water, although 

 the latter causes partial decomposition. Its aqueous solution is precipi- 

 tated almost entirely on acidulating it with hydrochloric acid ; but the 

 salt is soluble in concentrated hydrochloric acid, especially when warm, 

 forming a purple solution. On boiling this the salt is rapidly decomposed 

 and the colour chauges to a dirty green. 



Analysis of amido-diimido-orcin hydrochloride. — -428 grm. substance, 

 dried in vacuo, lost '035 grm. when heated to 100°, corresponding to 8-41 

 per cent, water. 



I. '255 grm. substance, dried at 100°, gave -180 grm. argentic chloride. 



II. -232 grm. substance, dried at 100°, gave -164 grm. argentic chloride. 



III. -344 grm. substance, dried at 100°, gave -242 grm. argentic 

 chloride. 



Theory. I. II. III. Mean. 



C 7 H 10 N 3 O 2 = 168 82-55 



CI = 35-5 17-45 17-47 17-49 17-40 17-45 



203-5 100-00 



These results correspond nearly to the formula 



C 6 (CI1 3 ) (NH 2 ) (NH) 2 (H0 2 ) HC1 



for the substance dried at 100° ; and the formula 



C 6 (0H 8 ) (NH 2 ) (NH) a (HO) 2 HC1 + H 2 O 



requires 8*13 per cent, water, and would therefore appear to be that of 

 the substance dried in vacuo. 



Amido-diimido-orcin sulphate . — This salt is readily prepared by precipi- 

 tating a dilute solution of the acetate with sulphuric acid, when it forms 

 minute lustrous plates which are purple by reflected light. By slow 

 crystallization from a hot aqueous solution it may be obtained in large 

 leaf -like plates. It somewhat resembles the hydrochloride in its proper- 

 ties, but is much less soluble in water. 



Analysis of amido-diimido-orcin sulphate. — I. *255 grm. substance, dried 

 at 100°, gave -128 grm. barium sulphate. 



II. -284 grm. substance, dried at 100°, gave -143 grm. barium sulphate. 



