Narrative of a journey in the interior of China, and of a voyage to and from that country, in the years 1816 and 1817 : containing an account of the most interesting transactions of Lord Amherst's embassy to the court of Pekin and observations on the countries which it visited.
By Clarke Abel, F.L.S. and Member of The Geological Society, Chief Medical Officer and Naturalist to the Embassy. London : Printed for Longman, Hurst, Rees, Orme, and Brown, Paternoster-Row. 1818.
Besides the plants already mentioned, I here saw the different varieties of the tea plant, of which it has often been asked me since my return, whether there be more than one species. This question I have not been able satisfactorily to answer, although I had little doubt, when examining the different plants, that there were two species; but I could not at the time define their characters, and have since lost the specimens through which I had expected to establish them. It may, however, be remarked, that the plants which had been brought from the black and green tea districts, differed in the form, colour, and texture of their leaves ; those of the green tea plant being longer, thinner, and of a lighter colour than those of the black, although growing in the same soil : this difference of character I also observed in a large tea plantation near Macao.
I could gain no information in China inducing me to believe that the process there used in manufacturing the leaf differs materially from that employed in Rio Janeiro, [note: the Emperor of China seems to have sent Chinese workers to Brazil's tea fields, planted using seeds sent some years earlier, in 1812] and which appears to be nearly the same as that of Japan, described by Kaemfer. From persons perfectly conversant with the Chinese method, I learnt that either of the two plants will afford the black or green tea of the shops ; but that the broad thin-leaved plant is preferred for making the green tea. As the colour and quality of the tea does not then depend upon the difference of species, it must arise from some peculiarity in the mode of manufacturing them. Drying the leaves of the green tea in vessels of copper has been supposed, but apparently without foundation, to account for the difference in colour. Without going into the supposition that any thing extraneous or deleterious is used, both difference of colour and quality may perhaps be explained, by considering one of the known circumstances attending its preparation ; namely, the due management of the heat used in drying the plant. There can be little doubt, that a leaf dried at a low heat will retain more of its original colour and more of its peculiar qualities than one that has suffered a high temperature. Supposing, therefore, the leaves of the same species or variety of the tea plant to have undergone such different degrees of heat in their preparation, their peculiar properties would be expected to occur of greatest strength in those of the greenest colour ; or in those to which both Chinese and Europeans attribute the most powerful properties. I may here add, that by far the strongest tea which I tasted in China, called " Yu-tien," and used on occasions of ceremony, scarcely coloured the water. On examining it with a view to ascertain the form of the leaves, I found it to consist of the scarcely expanded buds of the plant.
The question whether the tea plant will thrive in any other country than China, has in a great measure been settled by the success of the tea plantations at Rio under very little encouragement. It may be worth, however, considering what are the countries in which it is most likely to succeed, from their relation to its natural places of growth. The green tea district in the province of Keang- nan is embraced between the twenty-ninth and thirty-first degrees of north latitude, and is situated at the north-western base of a ridge of mountains which divides the provinces of Che-keang and Keang- nan. The black tea district, in the province of Fokien, is contained within the twenty-seventli and twenty-eighth degrees of north latitude, and is situated on the south eastern declivities of a ridge of mountains dividing the province of Fokien from that of Keang-si. Thus the whole range of the great tea districts of China, from the lowest to the highest degree of latitude, is from twenty-seven to thirty-one. But although these are the two districts from which the tea consumed in Europe is derived, the plant also flourishes in much higher latitudes. According to the Missionaries, it thrives in the more northern provinces of China ; and from Kaemfer it would appear, that it is cultivated in Japan as far as forty-five north latitude. All the known habitats of this plant are consequently within the temperate zone. Looking then to the latitudes in which the tea is cultivated with success, and especially to those of the great black and green tea districts, the Cape of Good Hope would seem to be the most eligible geographical situation for its culture ; and perhaps would be also found the most favourable with respect to soil.
It appears, from every account given of the tea plant, that it suc ceeds best on the sides of mountains, where there can be but little accumulation of vegetable mould. Our opportunities of seeing its cultivation were few, but were all in favour of this conclusion. Its plantations were always at some elevation above the plains, in a kind of gravelly soil formed in some places by disintegrated sand- , stone, and in others by the debris of primitive rocks. A large and flourishing plantation of all the varieties of the plant brought together by Mr. Ball, the principal tea inspector at Canton, is situated on an island close to Macao in a loose gravelly soil, formed by the disintegration of large-grained granite. Judging from specimens collected in our route through the province of Keang-nan, whence the green tea is procured, its rocks consist chiefly of sandstone, schistus, and granite. As to what may be the exact nature of the rocks of the black tea country in the province of Fokien, I have no precise information. But as the great ridge separating that province from Keang-si is a continuation of the one dividing the latter from Canton, it is perhaps legitimate to conclude, that their constituent rocks are the same ; and that the hills and soil on the eastern are the same as we found them on the western side of the ridge, or that they are covered by a soil like that in which the Camellia flou rishes. If this reasoning be just, the land forming the Cape being composed of the same class of rocks, namely, granite, schistus, and sand-stone, and of the same kind of soil that constitute the tea districts of China, would be scarcely less favourable with regard to structure than geographical situation for the culture of the tea plant.
But although the tea plant might for these reasons succeed better at the Cape than in many of our other dependencies, the success of the American plantations proves that it will assuredly flourish on the verge of the tropics. That it will also grow vigorously within them, is suf ficiently evinced by the fine plants which thrive in Sir Hudson Lowe's garden at St. Helena. But in both these situations, it seldom experiences a very high temperature. In Rio Janeiro the botanic garden is situated near the sea-shore, and receives the full influence of the land and sea breezes which blow during the greater part of the twenty-four hours. On the hills of St. Helena, freshened by the trade winds, the thermometer ranges from sixty-four to seventy-six degrees. The principal circumstances therefore to be kept in view in cultivating the tea plant are to obtain for it a meagre soil and a moderate temperature; and these may always be found on the mountains of tropical islands, and on the inland hills of temperate continents.
With respect to the management of the plant whilst growing, and the gathering of its leaves, there is not, I apprehend, much that is necessary to be learnt. From the general statement of authors it appears, that after the seed is once committed to a favourable soil, little subsequent attention is required. A few plantations of green tea, seen by the Embassy in Keang-nan, consisted of very low plants, perhaps kept down by pruning ; as the Missionaries tell us that the plant of the green tea districts is never allowed to grow to a large size; but that in the black tea country it is suffered to attain its full height, which sometimes reaches to ten or twelve feet. In collecting the leaves the principal circumstances that seem neces sary to be attended to are, to gather them at the proper seasons, to select the young leaves for the superior kind of tea, and the older leaves for that of inferior quality. The many varieties of tea seen in this country are doubtless the produce of the mixture of teas of different qualities, after their arrival in England.
But granting that the preparation of tea is more complicated than there is reason to suppose, it might doubtless be obtained from the proprietors of tea plantations who frequent Canton during the tea sales ; and is perhaps even now in the possession of many Europeans. If ever it shall suit the policy of this country to derive the tea from any of our own dependencies, there can be no doubt that we shall cease to be indebted to China for an article that enters so essentially into the comforts of all classes of my countrymen. I have heard much of the difficulty of transporting plants from China, in sufficient numbers, and in such health as to give a fair chance to any experiment for their cultivation ; but cannot imagine where that difficulty lies. A great number of plants which were on board the Alceste for the purpose of being left at the Cape and at St. Helena, were in the most vigorous state the day previous to the wreck, and there can be no doubt would have arrived thus at their places of destination.
Whether the leaves of many other plants would not attain the same quality as the tea, if submitted to the same process, is at least doubtful. Du Halde has remarked, that all the plants called Cha or Tea by the Chinese, are not to be considered as the tea plant ; and states, that a vegetable preparation sold in Shan-tung as very superior tea, is only a species of moss common to the mountains of that province. That the Chinese drink an infusion of ferns as tea is certain, as these plants were sold for the ex press purpose at Nan-chang-foo on the Po-yang lake. I cannot help suspecting that they employ the leaves of the Camellia in the same way. This plant bears the same name as the tea with the Chinese, and resembles it in most of its botanical characters, grows with it in the same district, and is I suspect cultivated in the same manner: the seeds of both produce oil. Kasmfer informs us, that a species of Camellia is used in Japan to give a high flavour to tea. Whatever observations I have made relative to the probability of the successful cultivation of the tea plant, equally applies to the Camellia oleifera, or oil plant. I cannot but believe, from what I have observed of the soil and climate of St. Helena, that many of its present barren hills might be covered with this elegant and valuable shrub.