418 THE EXAMINATION OF EUCALYPTUS KINOS, 



100-0 

 Tannic acid determination (Lowenthal), 55-5 per cent. 



Eucalyptus maculata, Hook., B.F1. iii. 258. 



The " Spotted Gum " of New South Wales and Queensland. 



I am only aware of the existence of two previous analyses of 

 this kino, but they differ exceedingly, and in the absence of the 

 fullest details of the kinos, one cannot institute comparisons 

 between them. 



According to Mr. Staiger (quoted in Dr. J. Bancroft's " Contri- 

 butions to Pharmacy from Queensland "), " this kino is entirely 

 soluble in boiling water to the extent of 60 per cent. It contains 

 benzoic acid in an impure state, and catechin. The gum insoluble 

 in water is of a sticky nature. When dissolved in alcohol, and 

 the solution evaporated in the air without artificial aid, a sticky, 

 clear, reddish-brown, tasteless gum remained. If this is treated 

 with ether, the sticky part of the gum goes into solution, and a 

 dry, clear, reddish, tasteless gum remains possessing the qualities of 

 shellac." 



Mr. F. N. Grimwade (JPharm. Journ. [3], xvi., 1102)says of a 

 sample, "Soluble in rectified spirit to the extent of 80*85 per 

 eent. ; cold water dissolved 18*9 per cent. Warm water extracted 

 ' a slightly higher percentage.' The amount of volatile constituents 

 was determined to be about 7*07 per cent., and consisted almost 

 entirely of water, with the merest trace of a volatile oil, to which 

 the peculiar aromatic odour, strongly resembling styrol, possessed 

 by the gum, is due. By steam distilling 2 or 3 drops of this oil 

 were obtained from about three-quarters of a pound of gum. ' I 

 found no trace of either benzoic or cinnamic acids in the gum.' 



" The tannic acid was found to be nearly allied to if not 

 identical with querco-tannic acid, giving the blue-black precipitate 



