CHAPTER XXIX

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CHINCHONA-CULTIVATION.

Ceylon--Sikkim--Bhotan--Khassya Hills--Pegu--Jamaica--Conclusion.

The complete success which has attended the cultivation of chinchona-plants in the Neilgherry hills, encourages the hope that similar happy results will follow their introduction into other hill districts of Southern India, which have been described in more or less detail in previous chapters. I have no doubt of the suitability of the Pulney hills, the Koondahs, the Anamallays, and Coorg for such experimental cultivation; and trials should hereafter be made on the Mahabaleshwurs, the high hills east of Goa, the Baba-bodeens, Nuggur, Wynaad, the Shervaroys, and the mountains between Tinnevelly and Travancore.

The hill districts of the island of Ceylon, which have the necessary elevation, and are within the region of both monsoons, also offer peculiarly favourable conditions for the cultivation of chinchona-plants, probably equal to the best localities on the peninsula of India. Mr. Thwaites, the Director of the Royal Botanical Gardens at Peradenia, takes a deep interest in this important measure, and under his auspices there can be no doubt of its ultimate success. It was from the first determined to send a portion of the chinchona-seeds to Ceylon, although the whole expense of the undertaking has been borne by the revenues of India, and no assistance whatever has been given by those colonies which will thus profit by its success.

The gardens at Peradenia are 1594 feet above the level of the sea, and the following table will give a correct idea of the climate:--

---------------------------------------------------------------------- OBSERVATIONS taken at PERADENIA, in Ceylon, in 1857. ----------+--------------------+----------+--------------------------- | Thermometer. | Rainfall | +------+------+------+ in | MONTH. | Max. |Mean. | Min. | inches. | REMARKS. ----------+------+------+------+----------+--------------------------- 1857. | | | | | | | | | | January | 82 | 79.3 | 74.7 | 1.8 |{ Fine and sunny. Cold dewy | | | | |{ nights and foggy | | | | | mornings. February | 82.5 | 79.8 | 76.5 | 1.3 | Do. do. do. | | | | | March | 84.2 | 82 | 77.5 | 5.8 |{ A few showers of rain in | | | | |{ the evenings. | | | | | April | 86.5 | 81.9 | 77.5 | 8.4 |{ Rain in the latter part | | | | |{ of the month. | | | | | May | 82.5 | 81.5 | 75 | 4.7 |{ Showery, with occasional | | | | |{ gales of wind. | | | | | June | 82.5 | 81.1 | 75.5 | 6 | Showery. | | | | | July | 80.5 | 77.1 | 75.5 | 9.8 | Continued rain. | | | | | August | 81.5 | 79.2 | 77.5 | 6.4 | Showery, with high winds. | | | | | September | 82.5 | 78.8 | 75.5 | 7.2 | Rainy. | | | | | October | 81.5 | 78 | 74.5 | 14.9 |{ Rainy, with occasional | | | | |{ sunshiny days. | | | | | November | 82 | 77.9 | 73.5 | 22.3 | Heavy rain. | | | | | December | 81.5 | 78.6 | 75.5 | 2.8 |{ Fine. Cold nights and hot | | | | |{ days. | | | +----------+ | | | | 96 | ----------+------+------+------+----------+---------------------------

It is evident that Peradenia is far too low and hot for chinchona cultivation. The _C. succirubra_, and some other species, would probably grow to fine large trees there, but the bark would be very thin, and would yield little or no febrifugal alkaloids. But there are many other localities in Ceylon admirably suited, from their elevation and climate, for this cultivation, and sites may be selected, well adapted to the different species, from 5000 feet to Pedrotallagalle, which is 8280 feet above the sea. Among these is the Government garden of Hakgalle, at Nuwera-ellia, which is 6210 feet above the sea, in a climate with an annual temperature of about 59° Fahr., and abundantly supplied with moisture. Here most of the chinchona-plants have been established under the superintendence of Mr. Thwaites, who is assisted in their cultivation by Mr. McNicoll, a zealous and intelligent gardener from Kew. Mr. Thwaites reported, last September, that the progress of the important experiment in the cultivation of chinchonæ was satisfactory.

In February 1861 the first instalment of chinchona-seeds arrived in Ceylon, being a parcel of the "grey-bark" species sent from the Neilgherry hills by Mr. McIvor; and soon afterwards a portion of the "red-bark" seeds was received. In April six plants of _C. Calisaya_ were transmitted from Kew, but two only survived, and are now growing vigorously at Hakgalle. Last September eight cuttings had been taken from them, two of which had rooted. From the seeds received early in 1861, 800 plants had been raised last September, namely, 530 of _C. succirubra_, 180 of _C. micrantha_, 25 of _C. Peruviana_, 45 of _C. nitida_, and 60 of the "grey-bark" species without name.

In January 1862 I forwarded parcels of seeds of _C. Condaminea_ and _C. crispa_ to Mr. Thwaites; and early in March six Wardian cases filled with chinchona-plants, from the depôt at Kew, were shipped for Ceylon.

Chinchona cultivation in Ceylon has thus been fairly started. It is exceedingly gratifying to hear that many coffee-planters will be glad to try the experiment upon their estates;[532] and that Mr. Thwaites will shortly be in a position to distribute plants from the Hakgalle garden.[533]

Chinchona-trees, in their wild state, have never been found at a greater distance than one thousand miles from the equator, and they are essentially inter-tropical plants; though they only flourish at considerable elevations above the sea. The reason appears to be that one of their chief requirements is a tolerably equable climate throughout the year, which the temperate zones, with their great differences of temperature between winter and summer, do not afford. For this reason sites were selected, in the first instance, both in India and Ceylon, within the tropics; and indeed this point was essential for the first experiments, because all the other conditions of the growth of chinchonæ could not have been found beyond the equatorial zone. Under cultivation, however, it is probable that, with other favouring circumstances, these plants might thrive within the temperate zone, at short distances from the tropic, and attention was naturally drawn to the hill districts of the Eastern Himalayas, in Bengal. The usefulness and importance of the introduction of the chinchonæ into India will be much enhanced if their cultivation can be extended to these regions, and attempts will, therefore, be made to form chinchona plantations in Sikkim, Bhotan, and subsequently in the Khassya hills.

The province of Sikkim,[534] at the base of the mighty Himalayan peak of Kunchinginga, consists entirely of the basin of the river Tista, which, with its tributaries, drains the whole country. Its position, opposite to the opening of the Gangetic valley, between the mountains of Behar on the one hand and the Khassya hills on the other, exposes it to the full force of the monsoon. Its rains are, therefore, heavy and almost uninterrupted, accompanied by dense fogs and a saturated atmosphere throughout the year. There are frequent winter rains accompanied by cold fogs, alternating with frost, hail, and snow. March and April are the driest months, but rains commence in May, and continue with little intermission until October. The bounding mountains are very lofty, and snow-clad throughout a great part of their extent; but the central range in Sikkim, which separates the Tista from its great tributary the Rangit, is depressed till very far into the interior. The rainy winds have thus free access to the heart of the province.

The snow-level is at 16,000 feet; and the mean monthly temperature of the English hill station at Darjeeling, which is 7430 feet above the sea, and in lat. 27° 3´ N., is as follows:--

----------------------------- DARJEELING. +------------+--------------+ | MONTH. | Mean | | | temperature. | +------------+--------------+ | January | 40 | | February | 42 | | March | 50.7 | | April | 55.9 | | May | 57.6 | | June | 61.2 | | July | 61.4 | | August | 61.7 | | September | 59.9 | | October | 58 | | November | 50 | | December | 42 | +------------+--------------+

The annual rainfall is 122.2 inches.

Of course no chinchona-plant would flourish in such a climate; and in the latitude of 27° it will be necessary to seek for suitable sites in much lower situations than in the hill districts of Southern India, which are in corresponding latitudes to those of the chinchona forests. In the Neilgherries the sites have been selected at the same altitudes as those at which the plants are found in South America, but in the Eastern Himalayas the localities must probably be chosen upwards of a thousand feet lower for each species--the _C. Condaminea_ and its companions perhaps at 5000, and the _C. succirubra_ between 3000 and 4000 feet.

From the sea-level to an elevation of 12,000 feet Sikkim is covered with a dense forest, consisting of tall umbrageous trees, often with dense grass jungle, and in other places accompanied by a luxuriant undergrowth of shrubs. In the tropical zone _Myrtaceæ_, _Leguminosæ_, and tree-ferns are common, and the air is near saturation during a great part of the year. _Vaccinia_ are found at from 5000 to 8000, and snow occasionally falls at 6000 feet. A sub-tropical vegetation penetrates far into the interior along the banks of the great rivers, and tree-ferns, rattans, plantains, and other tropical plants are found at 5000 feet, in the Ratong valley.[535]

I should conjecture that the extreme limit for the growth of the hardier species of chinchonæ, in Sikkim, will be found where their constant companions the tree-ferns and _Vaccinia_ end, namely at 5000 feet; and that the best sites for such species as _C. Calisaya_ and _C. succirubra_ are about 1000 to 2000 feet lower, amidst the sub-tropical vegetation of the valleys.

Bhotan, which adjoins Sikkim on the east, is a mountainous district of much the same character. In its western part the mountain ranges are lofty and rugged, and the river-courses very deep and generally narrow. The climate is equable, and the humidity of the winter appears to increase in the part adjoining Sikkim. The steepness of the mountains, and the influence of the elevated mass of the Khassya hills to the south, make the lower slopes, which skirt the plains of Assam, drier than those more to the eastward. Deep narrow valleys carry a tropical vegetation very far into the interior of Bhotan, among lofty mountains capped with almost perpetual snow. These attract to themselves so much of the moisture of the atmosphere, that the bottoms of the valleys are comparatively dry and bare of forest. The flora resembles that of Sikkim.[536]

The Khassya hills in 25° N. lat. form an isolated mass, rising up from the plains of Assam and Silhet to a height of 6000 feet. They rise abruptly from the plains of Silhet to the south, and at 3000 feet tree vegetation ceases, and is succeeded by a bleak stony region, with a temperate flora, up to 4000 feet, where the English station of Churra Poorji is built. The table-land is here three miles long by two, to the eastward flat and stony, and to the west undulating and hilly. On the south there are rocky ridges of limestone. The southern side of the hills is exposed to the full force of the monsoon, and the rainfall is excessive, as much as 500 or 600 inches annually. Further in the interior the fall is less, and it gradually decreases until the valley of Assam is entered. This great rainfall is attributable to the abruptness of the mountains to the south, which face the Bay of Bengal, and are separated from it by 200 miles of Jheels and Sunderbunds. The heavy rains on the Khassya hills are quite local, as in Silhet the fall is only 100 inches. The plateau presents a bleak and inhospitable aspect, and there is not a tree, and scarcely a shrub to be seen, except occasional clumps of _Pandanus_. This desolation is caused by the furious gales of wind, and the extraordinary amount of rain which washes off the soil. The valleys are open, though with deep flanks, and the hill-tops are broad. The grassy slopes to the north are covered with clumps of shrubby vegetation, and the forests are confined to sheltered localities. Though the rainfall on the southern side is 600 inches, twenty miles inland it is reduced to 200 inches. The mean annual temperature of Churra Poorji is 66°, and in summer the thermometer rises to 88° and 90°. To the westward of the Khassyas lie the Garrows, which do not attain a greater height than 3000 to 4000 feet.[537]

The flora of the Khassya hills bears a greater resemblance to that of the hills in Southern India than to the Sikkim and Bhotan types. Genera and species forming masses of shrubby vegetation are identical with those of the Neilgherry _sholas_. It is probable that chinchona-plantations, especially of _C. succirubra_, might hereafter be formed advantageously on the northern slopes of the Khassyas, but it is evident that the best chances of success for the species growing at great altitudes, in South America, are offered in the Himalayan districts of Sikkim and Bhotan.

With a view to the establishment of chinchona-plantations in the Eastern Himalayas, plants have been forwarded by Mr. McIvor to the Botanical Gardens at Calcutta. On January 19th, 1862, there were at Calcutta 91 plants of _C. succirubra_, all except four supplied by Mr. McIvor; six of _C. Calisaya_ from Java, and 133 of "grey-bark" species, of which 106 were supplied by Mr. McIvor, and twenty-seven were raised from the original South American seeds. Altogether there were 230 of the valuable species of Chinchonæ, besides fifty-nine of the worthless _C. Pahudiana_. It is intended to commence a chinchona plantation on the lower and outer range of Darjeeling in Sikkim at once, with a propagating-house on the model of Mr. McIvor's at Ootacamund; and afterwards to form a nursery for species growing at lower elevations on the Khassya hills.

There is another region in our Eastern dominions where suitable localities may be found for the cultivation of chinchona-plants, but it is as yet too little explored, and the difficulties of obtaining supplies, labour, and transport would be too great at present to allow of the possibility of forming plantations for some years to come. I allude to the recently formed province of Pegu. Dr. Brandis, the Conservator of Forests in Pegu, reports that it will be preferable to delay the introduction of chinchona-plants into that province, until their cultivation shall have proved successful in other parts.

In Pegu there are four great mountain ranges, running parallel with the sea-coast, which separate the valleys of the principal rivers. Commencing from the eastward, the first range is the Arracan-Yomah, dividing Arracan from Pegu, which is not higher than 4000 feet. The Pegu-Yomah, the principal seat of the Pegu teak, which separates the valleys of the Irrawaddy and the Sitang, only has a mean elevation of 2000 feet. The third range consists of the Martaban and Tenasserim coast-ranges, and barely attains a height of 5000 feet. The fourth and most eastern range, forming the watershed between the Sitang and Salween rivers, extends into the large and compact mountain mass of Yoonzaleen, to the south-east of Toungoo. The area of this lofty region is a hundred square miles, and several peaks rise to a height of 7000 and 8000 feet above the sea. The rains are heavier on these hills than on the adjacent plains, and the temperature is much cooler and more uniform. The formation consists of granite, gneiss, and quartzite. Up to 3000 feet the vegetation is of a tropical character, at which elevation teak disappears, and pines (_Pinus Khasyana_) begin, and go up to 5000 feet on dry gravelly soil. There are plenty of small mountain streams on these hills, with running water throughout the year; and the valleys and slopes are covered with evergreen forest.[538]

The Yoonzaleen hills are doubtless the best localities for chinchona-plantations in Pegu, but as yet there are no facilities for taking any steps with a view to the introduction of these inestimable trees, which will hereafter be as great a blessing to the fever-haunted jungles of Pegu as to those of India. The Yoonzaleens are forty miles from the town of Toungoo, which is at a distance of fifteen days of river navigation from Rangoon; and until a Sanatarium is formed on those hills, or some European settlers have established themselves there, it will be useless to attempt the introduction of the chinchona-plants. Before many years, however, it is to be hoped that plantations on the Yoonzaleen hills will supply quinine-yielding bark to the inhabitants of the plains of Pegu.

In a former