BY JOSEPH LAUTERER, M.D. 87 



coffee tannic acid. Allen puts it down as identical with tea 

 tannin. The tannin is present in the dry leaves at 1-5 percent., 

 and it differs from tea tannin by some essential reactions. The 

 blue colouration produced by ferric salt is turned intensely purple 

 by ammonia, the brown precipitate by copper acetate turns 

 violet on addition of ammonium carbonate, whereas tea tannin 

 gets green. Tartar emetic gives a slight precipitate, lead salts 

 give a white precipitate (tea tannin, brown), lime water gives a 

 white precipitate turning green (tea tannin turns blue). Boiling 

 with dilute hydrochloric acid yields a phlobaphene, and dry 

 distillation gives pyrogallol. 



The use of Paraguay tea is, in my opinion, to be preferred 

 by people of a nervous temperament, with a weak digestion and 

 a tendency to looseness, as it is weaker in cafiein and richer in 

 tannin than Chinese tea. 



As the Mate Tree is getting on so well here, acclimatisation 

 ought to be encouraged as much as possible. 



The Kola nuts, or the seeds of Sterculia acuminata, a native 

 of Guinea, in Africa, contain more caffein than the coffee beans 

 f2 per cent.), so that I entertained the hope to find some caffein 

 in the nuts of our Australian Sterculias. This hope has not 

 been realised, as I was not able to detect any caffein in the nuts 

 of Sterculia trichosiphon and S. quadrijida. The chemical con- 

 stituents of the African nuts seem to differ widely from those of 

 our seeds. The amylum grains of these are much smaller and 

 there is much more fat and much less tannin present in our 

 Sterculia seeds. The tannin of Kola nuts strikes green, that of 

 our Sterculias gets blue by ferric salts. 



Still, some other species might contain caffein. 



The easiest way for detecting it is by sublimation. If a few 

 drops of hydrochloric acid and a particle of potassium chlorate 

 are added to the sublimated alkaloid, it gets purple (after 

 drying) on addition of a little ammonia. 



As there are caffein-yielding plants in Asia, Africa, and 

 America, it is to be anticipated that we will yet succeed in 

 finding a similar plant in the Australian flora. 



