210 



outer portion. It powders fairh' well, and is more brittle and less librons than 

 the bark of ('. gltiitca. It is \'er\' nnieli rieher in tannni than an\' other Cci/lifris 

 bark, with the exception of C. (irciiosa, and although a thicker and darker 

 coloured bark than C. glauca, yet the extract was not comparatively more deeply 

 coloiired, considering the increased amount of tannin. ^Sce also article on the 

 tanning \-alue of CallHris barks in this work. ; 



Five samples of the bark of this species were determined : — 



I. This bark was collected from a tree j to 4 inches in diameter, at 

 \\'arialda, New South Wales, June, igog. The bark was beginning to thicken 

 even at this stage, and was somewhat deeply furrowed. Its greatest thickness 

 was 12 mm. It was blackish-grey externally, hard and compact, and 

 commencing to become corky in appearance, while in section the two layers were 

 well defined, the interior layer being yellowish in colour. Two determinations 

 were made with this sample, one with the whole bark, the other with the 

 " rossed " bark. 



The following results were obtained with the whole bark : — 

 Moisture ... ... 12-70 per cent. 



Total extract ... 37-03 „ 

 Non-tannin ... 6-10 ,, 

 Tannin 30-93 



The results with the inner " rossed " bark were: — 

 Moisture ... ... 12-6 per cent. 



Total extract ... 42-9 ,, 

 Non-tannin ... 6-8 ,, 



Tannin ... ... 36-1 ,, 



The information gained from the above determination indicates that the 

 larger amount of tannin is contained in the living portion of the bark ; so that 

 trees of medium size may be expected generally to contain the greatest amount of 

 tannin in their barks. 



II. This bark was taken from a tree 12 inches in diameter, collected at 

 Woodstock, New South Wales, in May, 1907. The exterior was blackish-grey 

 in colour, deeply furrowed, hard and compact, and the corky layer well defined. 

 Its greatest thickness was 30 mm. It was somewhat l)iittlc, and thus 

 powdered fairly well. Two determinations were made with this sample, in one 

 of which the extraction was completed with hot water, while in the other it was 

 carried out with cold water alone, eighteen hours being allowed lor extraction. 



