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APPENDIX IV. 



It was intended to give here the results of the examination of some tannin barks 

 yielded by Natal trees, but the work could not be completed, because some special 

 chemicals, required for the tannin determination (using a modification of Lowenthal's 

 method) and procured from Europe through a firm in Maritzburg, were found to be of a 

 different quality to that ordered, and had to be returned as unsuitable for even approxi- 

 mate analyses. 



The barks for -which it was intended to determine the percentage of tannin were the 

 following : 



1. Various species of Acacia. 



2. Elceodendron croceum (Saffraan). 



3. Ocotea bullata (Stinkwood). 



4. Curtisia Jaginea (Assagai). 



5. Rhizophora mucronata (Mangrove). 



6. Rhus longifolia. 



7. Rhus lucida (Taaibosch). 



8. Plectronia obovata. 



9. Protea hirta (Sugar bush). 



10. Protea lanceolata. 



11. Eugenia cordata (Waterboom). 



12. Colpoon compressum (Bergbast). 



all of which afford strong indications of the presence of tannic acid. 



