Jan. I, 18S7.] 



THE TKOPICAL AGRICULTURIST. 



453 



The following is the analysis of four of the samples : — 



Sulphate 

 quinine. Total. 



Red bark, G years natural 1-34 500 



„ „ renewed, 2 years 2-54 6-95 



„ „ 12 years, natural 2-43 741 



„ „ renewed, 2 years 2-71 7-01 



8. Thus it is seen that by renewing a 6-year-old 

 tree 90 per cent more of sulphate quinine is obtained, 

 and by working on a 12-year-old tree, only an increase 

 of 12 per cent takes place during the same period 

 of two years. With regard to the total alkaloids, it 

 should also be noticed that the shaving has made an 

 increase of 39 per cent in the younger tree, while 

 the older bark has somewhat deteriorated. One of 

 the most important features in these results is that 

 the renewed bark from the 6-year-old tree is superior 

 to the natural bark from trees of twice that age. 



9. I have had very few opportuniti'^s of observing 

 the effect of shaving on pure Ledger barks, containing 

 little, if any, alkaloid besides quinine, but it appears 

 that hybrid Ledgers of the broad-leaved variety holding 

 cinchonine, are capable of great improvement by the 

 shaving process as the following renewals of 11 mouths 

 will show compared with the natural bark of 6-year- 

 old trees : — 



Sulphate 



quinioe. Total. 



Ledger bark, narrow leaf, natural 1885 409 597 



„ „ „ renewed, 1886 6-62 8-49 



„ „ broad leaf, natural 1885 290 6-61 



„ renewed, 1886 519 80I 



10. The sulphate of quinine in the narrow-leaved 

 Ledger had increased 62 per cent and in the broad- 

 leaved Ledger 79 per cent the greater increase in the 

 latter variety is due to the presence of other alkaloids 

 which appear to develop quinine in the growth of 

 the tree. 



11. Shaving old trees has certainly not had a 

 beneficial effect from some trials made on Govern- 

 ment estates. Both red and crown trees from 16 to 

 21 years of age cannot well bear the removal of the 

 bark in this way and the renewal takes place slowly 

 and is impoverished instead of being enriched- A 

 crown bark was taken from Dodabetta aged 20 and 

 shaved. The shavings gave 3"66 sulphate of quinine ; 

 after six months some renewed shavings were taken 

 and found to j'ield only 1"85 per cent sulphate of 

 quinine, the bark then was commencing to decay and 

 the tree has since died. 



12. Experiment in manirriwj Cinchonas. — The effect 

 of manuring cinchona trees in order to stimulate their 

 growth and produce a greater yield of alkaloid has 

 been tried recently at Naduvatam. The first experi- 

 ment was made upon a succirubra of 7 years growth. 

 Cattle manure which had been previously kept for 

 some time in closed pits was applied some six 

 months before the bark was taken for analysis. A 

 sample of bark from a tree in the same plot, but 

 which had not been manured, was collected at the 

 same time for comparison. Two samples of magni- 

 folia bark were taken from trees which had been 

 manured in a similar manner to the succirubra ; the 

 first was 17 years, the second 20 years old, and samples 

 from unmanured trees were taken for comparative ana- 

 lysis at the same time. 



13. The results of the examination are tabulated 

 btlow: — 





3 



229 3'73 1-94 



o.^^ 



Succirubra manured 2 29 3'73 1-94 52 8'53 



,, unmanured 1-51 4-13 203 -32 799 



Magiiifolia 1 manured 378 3'90 -28 -82 8-78 



„ „ unmanured 3-13 439 58 '39 8-47 



„ 2 manured 2'59 3-49 1-21 '53 7'82 



„ „ unmanured 2'62 2'67 "67 '56 652 



14. It will be seen that the manuring has had the 



effect of increasing, in each instatioe, the aniouut of 



total alkaloids in the bark; and the quinine, the most 



important feature, has received a gain of 52 per cent. 



}u tbe succirubra; aad 20 per ceut. ia the &rst mag- 



uifolia. In the older magnifolia bark the quinine 

 remains about the same in quantity, and if no other 

 influences were at work, it might be inferred that 

 older trees are not so sensitive to the action of man- 

 ure as younger and vigorous-growing trees which have 

 not reached maturity. The food of such plants as 

 cinchonas which yield alkaloid in large quantity must 

 of necessity contain some nitrogenous element, and 

 as this must be taken from the ground it is only 

 fitting that a manure of this kind which contains 

 some constituents which are similar in their nature to 

 alkaloids should be supplied periodically to soils. Re- 

 garding the question from a commercial aspect the 

 higher value of the bark would cover the expense 

 of the manure and the cost of its application to the 

 land. The succirubra bark mentioned in the first ex- 

 periment, if the market price of the unit of quinine 

 were 4d, would realize eight pence per pound, whereas 

 the bark of the manured tree would be more than 

 one shilling per pound. I believe the effect of manu- 

 ring would be more apparent in Orown and Ledger barks 

 with large proportions of quinine in the total alka- 

 loids; in such cases, the extra outlay on manurial 

 agents, compared with the additional value of the 

 bark, would be much more remuneratire. 



15. Increase of Alkaloids ivith the a^e of trees. — A ques- 

 tion of much importance in cinchona cultivation is 

 the age to which trees should grow before the bark 

 can be profitably taken. To settle such an inquiry, 

 a large number of analyses of barks taken from trees 

 of all ages should be available, and in the following 

 tables I have made a selection of both Ledger and 

 red barks and have arranged them according to age. 

 Some of the figures are average of two or more ana- 

 lyses, and as the t\yo lists represent some forty 

 samples, I hope it will help to throw some light on 

 the subject. 



16. The first list comprises natural barks of the 

 narrow-leaved variety of C. Ledgeriana, and with one 

 exception, they all come from the "Wynaad district. 



17. The second list is by taking from my labor- 

 atory journal all those red barks whose ages have been 

 determined, whether they come from the Government 

 Plantations at Naduvatam or from private estates in 

 Wynaad, Ooorg or Travancore. 



Ledger Barhs, 



.' t« 



CO 



•= a'o c3-a H.a=;^s 



•55 -72 1-20 1^22 3-69 



•85 1-75 1-67 ^99 5'26 



108 1-65 1-15 -64 452 



113 203 1^79 -58 5'53 



1-0-2 2^64 1-78 ^50 594 



1^23 272 2^3rf -52 6^83 



1-32 215 311 -63 7^21 



1-31 3-22 218 ^71 7^43 



1-70 269 2^28 -93 760 



1-78 3-18 197 •SS- 7-40 



1-81 2^62 208 -90 7'41 



108 ^94 104 157 403 



•78 113 1-37 -97 4-25 



18. In the Ledger barks it wiU be noticed that there 



is a ptaady rise of quiuiue up to the age ot 



