Part 2

Among the different authors of any consequence that have written on the culture, preparation, and virtues of foreign teas, may be ranked Kampfer, Postlethwaite, Dr. Cunningham, Priestley, Lemery, Franchus, Meister, and Sigesbeck; as the limits of this Treatise will not permit a detail of observations from the whole of these writers, remarks can only be selected from the most principal of them. Most of the above, and many other, authors agree that the leaves are spread upon iron plates, and thus dried with several little furnaces contained in one room. This mode of preparation must greatly tend to deprive the shrub of its native juices, and to contract a rust from the iron on which it is dried. This may probably be the cause of vitriol turning tea into an inky blackness. We therefore do not think with Boerhaave, that the preparers employ green vitriol for improving the colour of the finer green teas. It may however be concluded, from the colour of bohea, souchong, and such as are called black teas, that they may be thus tinctured, by the means of vitriol, after they have been dried upon the iron plates in the furnace room; and this may likewise particularly cause that astringent quality which is more experienced in all the black than any of the green teas. According to Sigesbeck, the colours of these teas are artificial; so that if these pernicious arts are used even to give the tea a particular colour, there is no difficulty in ascribing the cause of their injurious effects.

That the native virtues of these teas are liable to considerable perversion is evident from the manner in which Meister relates they are prepared. He says the leaves are put into a hot kettle just emptied of boiling water, and that they are kept in this closely covered until they are cold, when they are strewed upon the hot plates above mentioned for drying. It is easy to conceive how the virtues of a leaf, however salutary by nature, must be destroyed by such a process. Being thus put into a steaming kettle, and suffered to remain there until they are cold, must cause the greatest part of their Virtues to evaporate, and the leaves to imbibe an unwholesome taint from the effluvia of the steaming metal. It cannot, therefore, be ascertained whether teas that are imported in Europe, after such a mutating preparation, have the least remains of their original odour or flavour, no more than they have of their qualities; but, on the contrary, it seems impossible but that the original nature of this shrub is entirely destroyed by an artificial preparation. Some falsely suppose that this species of management is only to soften such of the leaves as are grown too dry, and are therefore liable to break in the curling; but this will evidently appear not the cause, when it is considered that the greater part of the teas must dry in such a hot climate while they are gathering: and as they are particularly anxious to send them in as curious a curled state as possible, such teas must be thus moistened again, in order to curl them afterwards in that perfect manner which is performed on the iron plates of the furnace.

The opinion, therefore, of teas deriving their green colour from being dried upon copper being founded on a misrepresentation of the manner in which they are really prepared, a few observations upon the subject are indispensibly necessary. For those who have always understood that the detrimental qualities of foreign teas were the consequence of their being dried upon copper, may perhaps imagine they cannot be so pernicious if they were dried upon iron; but this opinion cannot be entertained by any persons who have the least knowledge of the manner in which the vegetable acid will corrode iron. Those who are acquainted with culinary processes must know in what manner the acid of onions will operate upon any steel instrument; it corrodes a knife so as to turn the onions black with the particles eaten away from the edge and the face of the blade. To avoid this unwholsome and unseemly inconvenience, a wooden instrument is generally used in all instances where onions form a part of the cookery appendages. It is consequently evident, that although iron utensils are now greatly used instead of copper, yet many injurious effects may happen from their being liable to be corroded by the acid of several vegetables. And if the nitrous acid of the air will corrode iron so as to cause rust, when it will not produce the proportionate effect upon copper, it is a demonstration that iron is the most liable to such a corruption. The corrosions of copper are undoubtedly pernicious; but the damage that tea would derive from its being dried upon sheets of this metal would not operate so injuriously to those who drink it as it does now by lying dried upon iron. For the latter bring more liable to the power of the mineral, vegetable, or animal acid, must impart more particles of its reduced calax to the tea than copper would. And, in order to shew how susceptible of corrosion iron is, the following instance is farther adduced: in Ireland, where some persons practise the art of tanning leather with fern, which possesses a very strong acid, particular care is taken to avoid using any iron vessels in the tannage, lest the colour of the leather should be blackened by the corroding particle of the metal. As it is the peculiar property of iron or steely particles, even in their most perfect state, to operate as too great an astringent for an aliment that is taken twice a day constantly, tea, when dried upon it, must be rendered proportionably pernicious. But admitting that the popular opinion of their being dried upon copper was just, the teas must be rendered proportionably injurious to the quantity of copperas or crude vitriol they imbibe from their acidity corroding the metal. Preparations of steel, that are, in many instances, considered as most salutary, yet in all pulmonary disorders the most eminent physicians have deemed them exceedingly dangerous. And in a country, like Great Britain, Holland, and other places, where a cloudy atmosphere, caused from their marshy soil or watery situation, renders most of the inhabitants subject to complaints of the lungs, foreign teas, contaminated by these iron corrosions, must be particularly detrimental. It is therefore, from these considerations, evident, that foreign teas, by being dried upon iron, have their bad qualities so increased as to render them the most pernicious of any morning and evening liquid that has yet been taken.----To return from whence we began this short digression.

It is remarkable that no satisfactory account has yet been given in what the bohea differs from the green tea. Dr. Cunningham, physician to the English settlement at Cimsan, and Kampfer assert, that the bohea is the leaves of the first collection.

This, however, being contrary to the general report of all travellers, that none of the first produce is brought to Europe, must be discredited; for these are all preserved for the Princes, to whom they are sold, even in China, at an immense price. Another proof is, that the boheas are brought here in the most considerable quantities, at a price greatly inferior to what even the second, third, and fourth crops are sold for in China. This not only evinces how inferior in quality the black tea must be, but also how little they are valued among those who must be acquainted with their properties.

Although the European dealers divide the green teas chiefly into three sorts, and the boheas into five, yet it is unknown from what province they are brought, of what crop they are the produce, and to which of the Chinese sorts they belong.

Added to their abuse of preparation may be that of their package. It is impossible but to know that their bad qualities must be considerably augmented by being so closely packed, for such a length of time, in such slight wooden chests, lined with a composition of wood and lead. Considerable quantities are likewise damaged by salt water and other causes, which, by the management of the tea dealers, are mostly mixed, and sold under different denominations. How the tea must be affected by the corrosion of the lead and tin by the marine acid, those of the least chemical knowledge will easily determine. To what danger must, therefore, the constitution of those who are in the constant habit of drinking such an empoisoned drug be exposed, may easily be imagined. Surely, when all these circumstances are considered respecting the pernicious mode of preparation, and particularly the poisonous qualities they are also liable to contract from the nature of their package, every person must be convinced to what a loss of health, if not of life, the constant use of such teas must expose them. Such evidence of their deleterious tendency is almost sufficient to alarm mankind against so prevailing an evil, without any further arguments; but as health is too precious not to require every possible proof that can persuade us to avoid what so immediately threatens our existence, the following arguments and testimonies of the bad qualities of foreign teas must not be omitted. Previous, however, to an investigation of their effects, it may be necessary to say a few words respecting

THE MANNER OF USING.

Foreign tea, as before observed, being taken as two principal meals of our daily aliment, is undoubtedly one great reason of the constitution of the people having suffered an entire change in its system. That vigour, spirits, and longevity, which characterised us in the last century, is totally subverted; disease, dismay, and debility, now lead us prematurely to the grave, where we end an existence too deplorable to excite the least desire for a longer continuance. Dr. Priestley states, very justly, in his Medical Essays, that it is curious to observe the revolution which hath taken place, within this century, in the constitutions of the inhabitants of Europe. Inflammatory diseases more rarely occur, and in general are much less rapid and violent in their progress than formerly; nor do they admit of the same antiphlogistic method of cure which was practised with success a hundred years ago. The experienced Sydenham makes forty ounces of blood the mean quantity to be drawn in the acute rheumatism; whereas this disease, as it now appears in the London hospitals, will not bear above half that evacuation. Vernal intermittents are frequently cured by a vomit and the bark, without venaesection, which is a proof that, at present, they are accompanied with fewer symptoms of inflammation than they were wont to be. This advantageous change, however, is more than counterbalanced by the introduction of a numerous class of nervous aliments, in a greater measure, unknown to our ancestors, but which now prevail universally, and are complicated with almost every other distemper. The bodies of men are enfeebled and enervated; and it is not uncommon to observe very high degrees of irritability under the external appearance of great strength and robustness. The hypochondriac, palsies, cachexies, dropsies, and all those diseases which arise from laxity and debility, are, in our days, endemic every where; and the hysterics, which used to be peculiar to the women, as the name itself indicates, now attacks both sexes indiscriminately. It is evident that so great a revolution could not be effected without the concurrence of many causes; but amongst these, I apprehend, the present general use of tea holds the first and principal rank. The second cause may perhaps be allotted to excess in spirituous liquors. This pernicious custom owes its rise to the former, which, by the lowness and depression of spirits it occasions, renders it almost necessary to have recourse to what is cordial and exhilarating; and hence proceeds those odious and disgraceful habits of intemperance with which too many of the softer sex of every degree are now, alas! chargeable. These are the sentiments of a character distinguished for his elaborate researches and judicious discoveries in almost every branch of liberal science. It may therefore be safely concluded, that the general manner of using India tea morning and evening has been, and is, the principal cause of the greater part of the diseases with which the natives of Europe are now afflicted. When it is considered that the first meal which is taken to recruit the body, after the loss it sustains from the insensible perspiration of the preceding night, and to prepare it for the avocations of the succeeding day, is India tea, who can be surprised that nature should rapidly become the victim of disease? Thus, instead of being supported by nutritious aliment, its nerves are enfeebled, its spirits diminished, and all its functions enveloped with the gloom of melancholy. Even in the afternoon, when nature is exhausted by care and fatigue, we fly for refreshment to tea, which, instead of bracing, still further relaxes the unnerved system. Such are the evil effects of the imprudent manner in which this pernicious drug is so constantly and universally used. But how must these evils appear in their extent, when the following view is taken of India teas, with regard to their variety of injurious EFFECTS.

In all the physical experiments that have been made upon India teas, there is, perhaps, none that shews its acid astringency more than one tried by the above writer, Dr. Priestley. Endeavouring to trace the differences and ascertain the astringency and bitterness of vegetables reciprocally bear to each other, he imagined he had found they were distinct and separate properties, by the following experiment: Taking two pieces of calf-skin just stripped from the calf, he immerged them in cold infusions of green and bohea tea; at the expiration of a week he found they were hard and curled up, and that there was no sensible difference between them. He therefore concluded, that this experiment afforded a striking proof of India tea differently affecting a dead and a living fibre; this he considered as the greatest effect of a medicine. But, with deference to so distinguished an author, I cannot but attribute this astringency of the skin to the particular properties of India tea; for all physical as well as medical experience proves that vegetable produce afford some that are astringent, and others that are relaxant, of the dead as well as the living fibre. Oak bark is equally astringent, and hardens the fibres of the hide, as well as it braces the living nerve of our bodies; therefore the effect produced by the India tea upon the dead skin only proves, what we have before related, that an infusion of it has a peculiar effect, which, being too frequently applied to the nerves, destroys their tensity by their fine fibres being either broken or relaxed by overbracing. Were any astringent to be constantly taken, it must ultimately produce more or less such an effect; so that while the above experiment of the learned Philosopher demonstrates that India tea has the power of astringing the dead as well as the living fibres, it does not prove that astringency bitterness are separate qualities. On the contrary, bitterness seems to be the characteristic taste of all that has the tendency to contract whatever is the subject of its application. Thus galls, bark, rhubarb, camomile tea, &c. &c. are all bitter and astringent. It is, therefore, the immoderate use of such an astringent that ultimately relaxes and debilitates: like the too frequent bracing of a drum, or any other stringed musical instrument, destroys its tensity, the body is unnerved by the overstretching of its fibres. Although we sometimes differ with the celebrated Doctor in part of the conclusion he has drawn from his experiment, yet the following sentiments so perfectly coincide with all our observations upon India teas, that we are happy to have the opportunity of corroborating our own with the sentiments of so eminent a Philosopher. He says, from his experiments, "it appears that green and bohea teas are equally bitter, strike precisely the same black tinge with green vitriol, and are alike astringent on the simple fibre. From this exact similarity in so many circumstances, one should be led to suppose that there would be no sensible diversity in their operation on the living body; but the fact is otherwise: green tea is much more sedative and relaxant than bohea; and the finer the species of tea, the more debilitating and pernicious are its effects, as I have frequently observed in others, and experienced in myself. This seems to be a proof that the mischiefs ascribed to this oriental vegetable do not arise from the warm vehicle by which it is conveyed into the stomach, but chiefly from its own peculiar qualities." Dr. Hugh Smith, in his Treatise on the Action of the Muscles, justly says, that an infusion of India tea not only diminishes, but destroys the bodily functions. _Thea infusum, nervo musculove ranae admotum, vires motices minuit perdit._ Newman, in his Chemistry, says, when fresh gathered, teas are said to be narcotic, and to disorder the senses; the Chinese, therefore, cautiously abstain from their use until they have been kept twelve months. The reason attributed for bohea tea being less injurious than green is, being more hastily dried, the pernicious qualities more copiously evaporate.

"Tea," says Dr. Hugh Smith, in his Dissertation upon the Nerves, "is very hurtful both to the stomach and nerves. Phrensies, deliriums, vigilation, idiotism, apoplexies, and other disorders of the brain, are all produced by the nerves being thus disarranged and debilitated. If the digestive faculty of the stomach be weakened, the body, failing of recruiting juices, must tend to emaciation, and the whole frame be rendered one system of distress and infirmity. The nerves, being thus deprived of a sufficiency of their animal spirits, must become languid, and leave every sense void of the first means of conveying to the mind the only enjoyments of our temporal existence.

"But if there be any class of persons to whom India tea is more particularly hurtful than to any other, it is that which includes the studious and sedentary, and especially those who are enfeebled with gout, stone, and rheumatism; age, accident, or avocation, cause many persons to be unfortunately ranked amongst those of the latter description. These, from their intensity of thought, want of exercise, injurious position of body, respiration of unwholesome air, and a variety of other causes, have not only their animal spirits exhausted, but their liquids corrupted from the loss of a necessary circulation. With these evils India tea operates as an absolute poison. Indeed, it frequently renders those incurable, who might, by other means, have been relieved.

"When a view is taken of the dismal effects produced by India teas, the mind seems to be bewildered in searching for the cause of using so generally a drug that is so universally destructive. It chiefly originated in a fundamental mistake of physical principles. About the time that India tea was introduced to Europe, a grievous error crept into the practice of medical professors; they falsely imagined that health could not be more promoted than by increasing the fluidity of the blood. This opinion once established, it is no wonder that mankind, with one accord, adopted the infusion of India tea, which was then a novelty to Europe, as the best means of obtaining the above effect. By the advice of Bentikoe chiefly was the pernicious custom of drinking warm liquors, night and day, established. To this man, and the introduction of India tea, may be ascribed that revolution in the health of Europeans which has happened since the last century. The present age, therefore, have great cause to lament, in what they suffer in nervous complaints, that their forefathers did not attend more to the scientific and judicious advice of the illustrious Duncan, Boerhaave, and the whole school of Leyden, who proscribed this error. Although they could not entirely prevent this physical abuse, yet their zealous endeavours did, in some degree, at first impede its progress; but, however, so powerful did novelty plead in favour of India teas, that, at last, general custom and prejudice bore away every barrier that had been erected by these learned and experienced physicians. This error, instead of diminishing, has increased: most valetudinarians are now of opinion that a thick blood is the sole cause of their complaints; with this impression they adopt what they call the diluent beverage of India teas. It can scarcely be imagined how many disorders this practice produces; it may be justly termed the box of Pandora, without even hope remaining at the bottom." Tissot says, "They are the prolific sources of hypochondriac melancholy, which both adds strength to and is one of the worst of disorders." He adds, "with regard to studious men, who are naturally weak and feeble, such warm beverages are more hurtful to them than to others; for they are not troubled with an over thick, but, on the contrary, too thin a blood. You are all aware," continues he, "respectable auditors, that the density of the blood is as the motion of the solids; the fibres of the learned are relaxed, their motions are slow, and their blood, of consequence, thin. Bleed a ploughman and a doctor at the same time; from the first there will flow a thick blood, resembling inflammatory blood, almost solid, and of a deep red; the blood of the latter will be either of a faint red, or without any colour, soft, gelatinous, and will almost entirely turn them to water. Your blood, therefore, men of learning, should not be dissolved, but brought to a consistence; and you should in general be moderate in the article of drinking, and cautiously avoid warm spirituous liquors.

"Amongst the favorite beverages of the learned," the same Tissot observes, "is the infusion of that famous leaf, so well known by the name of India tea, which, to our great detriment, has every year, for these two centuries past, been constantly imported from China and Japan. This most pernicious gift first destroys the strength of the stomach, and if it be not soon laid aside, equally destroys that of the viscera, the blood, the nerves, and of the whole body; so that malignant and all chronical disorders will appear to increase, especially nervous disorders, in proportion as the use of India tea becomes common; and you may easily form a judgment, from the diseases that prevail in every country, whether the inhabitants are lovers of tea or the contrary. How happy would it be for Europe, if, by unanimous consent, the importation of this infamous leaf was prohibited, which is endued only with a corrosive force derived from the acrimony of a gum with which it is pregnant."