470 



2 he Supplement to the Tropical Agricultu/nst 



the framework and some in the middle. More 

 water must then be put into the pit, until the 

 plant is all covered, and fermentation allowed to 

 proceed for 48 hours. After this the stones and 

 frame work of bamboos should be taken out 

 and the fermented plant be covered with 2—3 

 inches of soil. 



In about two months the manure can be dug 

 out and either be used at once, or kept heaped 

 up tor future use. 



The pit will thus be ready to take in another 

 lot of Indigo plant, which meanwhile will have 

 grown big enough for a second cutting. 



I estimate that three to four cuttings can be 

 obtained in Ceylon during the year, and the 

 Indigo manure thus obtained should have a 

 money value of about K100 to K.150 per acre 

 cultivated in Indigo, according to the quantity 

 of leaves cut. 



SCHROTTKY DE ScHROTTZYNSKI. 



Colombo, April, 1912. 



IS THINNING OUT RUBBER PLANTED 

 20 FT. BY 1 FT. N ECESSARY.? 



Kangala, May 4th. 



Dear Sir, — One hears agreatdeal now-a-days 

 on the above subject, and the more one hears 

 the more interested one becomes and doubtless 

 it is a matter that very closely concerns us. 



I mention the above planting distance for, I 

 believe, it has been generally adopted in Ceylon. 



I have visited many estates and at present 

 cannot see any reason for thinniDg rubber plan- 

 ted afc this distance, anyhow certainly not under 

 10 years of age, and the profit gained by tapping 

 trees from 6 — 10 years with rubber at 4s. 6d. a 

 lb. cannot justify thinning out unless it is 

 clearly seen that damage is being done. One 

 hears a lot of talk that thinning out at this dis- 

 tance is necessary, but can anyone prove it ? 



Further, thinning out may be dope in different 

 ways, some suggest cutting out every alternate 

 tree and others only those that are backward 

 and undeveloped, and this latter method ap- 

 pears more reasonable for one does not then 

 sacrifice a good tree for the sake of a bad one. 



I do not think it is the 1st or 2nd renewal of 

 bark one need be in fear of, but perhaps pos- 

 sibly the 3rd, and then this must also necessarily 

 depend on soil and the climate. 



A well-known Visiting Agent, I believe, is en- 

 tirely against thinning out rubber planted at 

 this distance, and it would be interesting to hear 

 opinions on this important matter. — Yours 

 faithfully, 



B. 



"HEVEA BRAZILIENSIS," OR PARA 

 RUBBER. 



THE FOURTH EDITION. 



By general consent this book by Mr Herbert 

 Wright, Assoc. r.c.s , f.l.s., is accepted as the 

 standard work on the cultivation of rubber. The 

 first edition, a small handbook of rather more 

 than 100 pages, was published by Messrs A M & 

 J Ferguson at this office in 1905, when the area 

 under Para rubber in the Middle East was esti- 

 mated at only 70,000 acres. Second and third 

 editions were speedily called for, and now that 

 the industry has developed into one of gigantic 

 importance a fourth edition has just been 

 issued, and the increased knowledge and im- 

 proved methods gained by experience are re- 

 flected in this new production. The new work 

 has beon re-written in nearly every section and 

 all information has been brought thoroughly up 

 to date. Several new features are added and the 

 work is well illustrated with Art plates. The 

 .text with indices extends to 530 pages and in- 

 cluding the commercial section the whole work 

 comprises ovqt 680 pages. 



The Growth of the Industry. 



The author says that, while writing this edi- 

 tion, he has been greatly impressed by the 

 changes which in recent times have come over 

 the plantation and crude rubber industry. At 

 the time of writing the previous editions in 1905, 

 1906 and 190S, he had the impression that the de- 

 velopment on plantations was, in many details, 

 in quite an experimental phase. Today this idea 

 must almost entirely be abandoned. The cultiva- 

 tion of rubber trees has proved itself to be equal 

 to, if not more important than, that of any other 

 plant grown in the tropical zone. The crops 

 from cultivated trees and the anticipated yields 

 have so impressed various governments that 

 many of them have decided to effect a radical 

 change in their agricultural policy. These gov- 

 ernments, which for many years have relied 

 upon large revenues from Brazilian and African 

 forests, have, though at a late hour, seen the 

 necessity of lowering export duties, subsidising 

 plantation developments and encouraging the 

 use of up-to-date methods and machinery in the 

 collection and preparation of rubber. While the 

 growth of the Eastern plantation industry has 

 led countries previously dependent upon wild 

 rubber to protect old, and foster new sources of 

 supply, other countries, especially Ceylon, Bor- 

 neo, the Federated Malay States and the Straits 

 Settlements have already reaped considerable 

 financial benefit from the sale of land and new 



