45- 



fM£ TROPICAL AORtCVLTVklST 



fjAN. 1, IBS'?. 



complete analyses of all the different species of 

 bark which were sent to the Colonial and Indian Ex- 

 hibition in London. Some experiments in renewing 

 bark and manuring trees are recorded ; and tables are 

 given showing the increase of alkaloids by growth, 

 and the deterioration of alkaloids by age and other 

 causes. The liquid cinchona which was partly made 

 last year has been completed. Most of the analytical 

 work has been done for Government, but several 

 barks have been received from private parties, and 

 I have to thank some of these gentlemen for infor- 

 mation respecting samples they sent, as this enabled 

 me to summarise results which are of general use- 

 fulness to planters. 



3. There have been six sales of Government bark 

 in Madras during the year, viz. September, October, 

 November, December, 1885, January and February 

 1886. Samples of the various kinds have been valued, 

 which has given a reserve price to the auctioneers, 

 but the competition being so brisk at each sale, these 

 prices were exceeded. 



I append a statement showing the qualities of barks 

 disposed of, their value in sulphate quinine, and the 

 value of the unit in pence. 



September 1885. 



Sulphate Value of 

 Description of Bark. quinine, unit. 



Per cent. d. 

 Dodabetta Natural Crown ... 4-18 4-0(5 



Naduvatam Root „ ... i-iQ 4-90 



October 1885. 



Dodabetta Renewed Crown ... 406 5 85 



„ Mossed ,, ... 4-70 5-48 



Naduvatam „ ,, ... 4-05 5-37 



„ Root „ ... 4-46 5-38 



November 1885. 



Dodabetta Natural Crown 4-18 6-70 



„ Branch „ 1-17 7-90 



„ Root „ 4-33 6-93 



NaduTatam Natural „ 3'52 7'10 



Renewed „ 4-22 7-52 



„ Branch „ 2 1(5 7-06 



December 1885. 



Dodabetta Natural Crown 3-10 6-69 



„ Mossed „ 4-73 555 



„ Renewed „ ... ... 6'5G 5'49 



January 1886. 



Naduvatam Natural Red 156 497 



February 1886. 

 Naduvatiim Renewed Red ... ... 2'54 4'62 



„ Root *„ 138 5-25 



4. These barks are, on the average, of the same value 

 as those sold last year, but with regard to the value 

 of the unit it will be observed that the market h«s 

 experienced a great fluctuation during the year. In 

 September the unit being 4-48r/, October b-o2d, Nov- 

 ember 7"20d, December 5'91(', January and February 

 4-94(/. 



Bark sent to Ixdivn and Coi-onial Exhibition. 



5. Renewal by shaving. — Shaving cinchona trees has 

 been for some years a method of harvesting bark which 

 in some districts works better than that of stripping and 

 mossing. The cellular and richer portion of the bark 

 is removed in this way and the fibrous portion is left. 

 The bark thus treated thickens again, and the shavings 

 taken from it are found to be richer still iu alkaloids. 

 The analyses of some succirubra shavings taken from 

 trees grown in the Ouchterlony Valley will show to 

 what an extent trees may be improved by this method- 

 The renewals had been taken after intervals of twelve 

 months ; the experiment, therefore, has lasted over 

 three years. 



Original Bark 



Once renewed 



Twice rentwed 



Thrice renewed 



0. The increase in ^ 

 second year by renewing is most satisfactory ; the 

 increase is not so prominent in the third year, but 

 the bark is good, and indicates that shaving for at 

 least four years might be permitted. The trees upon 

 which these experiments were made were six years 

 old, when the original bark was taken. If at this 

 comparatively early age they are not injured by shaving, 

 and renew their bark so well, it is not desirable to 

 wait for the trees to become more matured. 



7. When trees are allowed to grow uutil they are 

 over 12 years of age and then shaved, the renewal 

 sets in more slowly, and the resulting bark does not 

 compare more favorably with the original bark than 

 if the trees operated upon had been half that age. 

 This may be instanced by quoting some more analyses. 

 Last December some interesting samples were sent 

 by the Manager of the Glenrock Company, South-Eaat 

 "\Vynaad, consisting of some natural and renewed 

 shavings of succirubra takeu from trees of 6 and 1% 

 years of age, 



