, is a crystalline substance, melting-point 63°, boiling-point 276°-277°. The crystals are easily soluble in alcohol or ether, with difficulty in water. The least trace of nitrous acid strikes a yellow colour from the formation of triamidobenzol.
, is in the form of tabular crystals, melting-point 140°, boiling-point 267°. If this substance is oxidised with ferric chloride or manganese binoxide and sulphuric acid, chinone is produced; if treated with SH2 and ferric chloride, a violet sulphur-holding colouring matter, allied to methylene blue, is formed; these reactions are tests for the presence of the para-compound.
Both these diamines are poisonous. Metaphenylenediamine produces, in the dog, the symptoms of an aggravated influenza with continual sneezing and hoarse cough, which, if the dose is large enough, ends in coma and death. Paraphenylenediamine produces exophthalmia, the tissues of the eye undergoing complete alteration.[663]
[663] Comptes Rend., cvii. 533-535.
Both compounds, in doses of 100 mgrms. per kilo., cause more or less salivation, with diarrhœa. The para-compound is more poisonous than the meta-compound. So far as the author is aware, neither of these diamines have been separated with certainty from the urine of sick persons, nor from products of decomposition.