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bark of the older trees. The thickness of the bark was 2 to 3 mm. Tabout J inch"). 

 Externally it was dark grey and internally light yellowish in colour, and when 

 quite air-dried it powdered very well. The extract was excellent in its colour, 

 and was rapid in its action on hide powder, which was but little coloured 

 by the tannin. The amount of non-tannin was somewhat high for the bark 

 of this species, but this was to be expected from such young material. The com- 

 paratively large amount of 25 per cent, of tannin from air-dried bark stripped from 

 saplings i inch in diameter, together with the excellence in colour of the extract, 

 illustrates again the value of the bark of Callitris calcarata for tanning purposes. 

 It also shows that the material removed when thinning out for plantation purposes 

 has a considerable tanning value, which should not be neglected. 



The reactions given with the extract (25 grams per litre) were identical 

 with those given by the bark of this tree in all stages. The following results were 

 obtained with the air-dried bark : — 



Moisture ... 



.. 13-70 per cent. 



Total extract 



•■ 33-47 



Non-tannin 



.. 8-28 „ 



Tannin 



•• 25-19 



The total extract from the air-dried powdered bark, by cold water alone 

 during twenty hours' contact, was 24-5 per cent., and the non-tannins extracted 

 were considerably less in amount than when the bark was finally extracted with 

 hot water. 



Trees of this species about 3 to 4 inches in diameter seem to be in about 

 the best condition for stripping, as the bark then contains a maximum amount 

 of tannin, a comparatively small amount of non-tannin, and only a small quantity 

 of the external corky layer containing constituents of a dark colour. 



When a portion of the dried tannin was heated with glycerol to 210° C. 

 in the usual way, and extracted with ether, the aqueous solution of the ether 

 extract gave reactions as follows : — 



Ferric chloride, an olive-green colour. 



Lime water, red colour. 



Pine chip and hydrochloric acid, slight violet colour. 



It is thus evident that although somewhat intermediate in character, the tannin 

 of C. calcarata belongs to the catechol group. 



