Kitabı oku: «The Romance of Plant Life», sayfa 20
CHAPTER XXIV
RUBBER, HEMP, AND OPIUM
Effects of opium – The poppy-plant and its latex – Work of the opium-gatherer – Where the opium poppy is grown – Haschisch of the Count of Monte Cristo – Heckling, scotching, and retting – Hempseed and bhang – Users of haschisch – Use of india-rubber – Why plants produce rubber – With the Indians in Nicaragua – The Congo Free State – Scarcity of rubber – Columbus and Torquemada – Macintosh – Gutta-percha.
SUPPOSING that in China or Japan you meet a native who shows the following symptoms: —
(1) Eyes hollow and surrounded by a bluish margin; (2) pupils much dilated; (3) with a stupid appearance; (4) with an emaciated body; (5) of unsteady and staggering walk; (6) with a dreamy disposition; – then, you may be sure that he is an opium-smoker. In some of the Chinese provinces every man smokes ·03 to ·07 ounce of opium daily, but those who indulge to excess consume ·3 or even ·6 ounce. It is an excellent medicine when employed in a lawful and justifiable manner, for it calms the spirits and makes one sleep. But its use is always dangerous, even when employed in very small quantity, as in laudanum and morphia.
In the Fen country in England there used to be a very large sale of laudanum pills which keep off asthma and rheumatism, but even there it is a dangerous remedy, for it is only too easy to fall under the control of this drug either by injection of morphia, or by eating or smoking laudanum or morphia. De Quincey's Confessions of an Opium-eater and Kipling's Gate of the Hundred Sorrows give a lurid picture of the ruin of body and soul brought about by opium.
It is produced from the heads of the Opium Poppy (Papaver somniferum). Any poppy (or indeed any plant of the Poppy order) when scratched or wounded exudes a thick white or orange milky fluid. This is called "latex" (or milk); it is always more or less poisonous, and generally contains some sort of resinous matter. Thus when the plant is scratched or pierced, a drop of this milky latex comes out and at once hardens over the wound. Of course the plant is much benefited by this, for any destructive insect, unless it is a confirmed opium-eater, will be poisoned or killed; then also, if wounds are caused by wind, heavy rain, or animals passing, the scar is at once healed over and covered by the hardened opium, so that no dangerous fungus spores can get in to attack the plant. There is a mildew fungus and also a smut fungus (Entyloma) which attack the poppy, but both these enter by the stomata and live between the cells of the plant.
The general appearance of the Opium Poppy is quite familiar; its upright stems, large, clasping, bluish-green leaves and conspicuous flowers may be seen in many gardens. It is rather interesting, and in many ways; when young, the buds droop or hang down, and are entirely enclosed in two large green, hairy sepals. These last are soon thrown off, and then the flowers open out and display the petals with their rich black spots, and the crowded mass of stamens which surround the central greenish head. In bud these petals are "cramb'd up within the empalement by hundreds of little wrinkles or puckers as if three or four fine cambrick handkerchifs [sic] were thrust into one's pocket," as an old writer describes it (Grew).
Bees, and especially bumbles, are extremely fond of it, and even seem to be, in a way, opium-eaters, for they get quite exalted, almost intoxicated, and above their ordinary laborious selves. They scurry round and round the flower under the stamens or hover excitedly above it.
It is at this stage that the opium-gatherer begins his work; he goes round the beds and collects the petals of the poppy to use later on (see p. 304). The poppy-heads are then half grown and bluish-green, but they soon begin to turn yellow and ripen. When ripe they are most interesting to examine. There is a large platform covered by a radiating star-like ornament, which is the stigma. Underneath this is a circle of little holes just below the crown, but above the head. Each small hole has a flap. Now if you gather a ripe poppy-head on a fine dry day all these holes are open, and if you hold it upright and swing it vigorously from side to side the tiny seeds come flying out of the holes and will be thrown to a considerable distance. The stalk is supposed to swing in a high wind, and the seeds are really slung or thrown out of the holes. But if, when you come home, you put your poppy-head in water, or look at the plants in the garden on a very wet day, you will find that every hole closes or is shut up, because the small door mentioned above expands so as to close the opening.
The seeds are only sent out on a fine dry day; but they travel well. It was observed in America that certain poppies had been introduced as weeds at a certain place; in fifteen years they were found twenty-five miles farther on, so that they were colonizing the country at the rate of three-fifths of a mile per annum.134 The seeds themselves are very light and are of some value; they may be eaten like caraway-seed, as comfits, or crushed to supply an oil for lamps, or used as medicine. It is said that the value of the seed raised in France was in one year £170,000. The heads themselves are also valuable (they are worth 35s. per thousand), and even the dried stalks and leaves, for they may be used as fodder.
But the real reason why the plant is cultivated in so many parts of the earth is the great value of the opium obtained from it. This is gathered in the following curious way. As soon as the dew has dried off the plant, the cultivator goes round the beds and scratches every poppy-head with a tool made up of three knives tied together. That is the time recommended by Theophrastus, and it is apparently still the usual time to choose. In the late afternoon, from four to seven, he comes round again and scrapes off the congealed milk, which is then worked up into cakes and taken to the factory.
It is prepared by being kneaded, dried, and rubbed until it is of a pale golden colour.135 Finally, it is enclosed in a mass of poppy petals, sometimes mixed with the fruits of a kind of dock, and is then ready for export.
It is cultivated in a great many parts of the world – Turkey, Syria, Persia, France, China, the United States, Germany, Queensland, but especially in British India, where the immense plains at Malwa used to furnish opium worth about sixty million rupees annually (after deducting all expenses). This was mostly exported to China, and amounted to a tax of about threepence per head on every Chinaman; it was also sufficient to defray about one-sixteenth part of the expenses of our Indian Empire. The story of how Great Britain forced China to take our opium is not a creditable one nor agreeable to read. The plant was known in ancient Egypt, Persia, and Rome, and was used in China for at least two hundred years before our times.
What is supposed to be the original wild plant from which the opium poppy was derived seems to have been cultivated in the ancient Swiss lake dwellings, for the seeds of Papaver setigerum occur there in abundance. The price of the crop may amount to £90 or £120 per acre.
Another very ancient plant is the Hemp, Cannabis sativa. It was known to Herodotus, who says that "in the country of the Massagetæ there is a tree bearing a strange produce which they casting into a fire inhale its fumes on which they straightway become drunk." It is a tall, rather handsome annual, with stems from three to fifteen feet high. It is cultivated all over the world, from the Equator to 60° north latitude, but for different purposes. In India it is chiefly for the resin, "haschisch, churrus, bhang." (That was the drug used by the Count of Monte Cristo.) In Russia it is for the seed and the fibre that the plant is cultivated, and in France, Italy, and Austria the fibre seems to be the most important product.
Some of the plants produce only stamens or male flowers. The fibre given by these is stronger and more tenacious than that of the female plant, which, however, is finer and more supple. The fibre obtained from the cold northern districts of Russia is said to be the strongest of all.
The preparation of the fibre is a long, tedious, and laborious operation. It is also unhealthy, for the fibre has to be "retted" (steeped in water so that the soft parts decay), "scotched" (that is the hard wood must be broken and removed), and "heckled."
This last process is familiar to all who are interested in political matters. It consists of being drawn on hard points difficult to traverse and of a very fine and sharp character! Hemp is the commonest fibre for string, rope, etc.; it used to be employed for sailmaking by the Romans. Catherine de' Medici is said to have had two chemises made of hemp.
Hempseed is much appreciated by poultry and birds of all kinds (which makes both harvesting and sowing rather difficult); but the chief use of the seed is to furnish a fatty oil used for soft soap, lighting, and painting. The remains, after taking the oil, are employed as a cattle food, but it does not form a satisfactory cake.
The chief interest of hemp is, however, the drug that is made from the resinous juice. No doubt this has the effect of keeping off dangerous insects, for it is said that plants of hemp even keep off insects from other plants planted close beside them.
Sometimes the leaves and stalks are dried in order to make the drug "bhang." Many allusions to this substance are found in Eastern poetry, where it is called the "Leaf of Delusion," "Increaser of Pleasure," and "Cementer of Friendship," but madness is the result of addiction to its use.
The resin is collected by making the labourers put on leather aprons, and then run up and down vigorously through the hempfields. The resin is then scraped off the leather, or off their skins if they prefer to do without leather. It is either eaten or smoked. Burton describes how at every cottage door in East Africa the Arabs may be seen smoking bhang with or without tobacco. "It produces a violent cough ending in a kind of scream after a few long puffs." In small doses haschisch (resin) has pleasant effects, for people experience pleasant illusions, good appetite, excitement, and laughter, followed, however, after an interval by stupor and sleep.
People addicted to the use of haschisch roll their eyes violently, and have a wild, startled appearance.
Naturally so dangerous a drug cannot be recommended unless under the most exceptional circumstances, but it is employed in cases of asthma and insomnia. Haschisch and opium are the two great curses of the Chinese, Malays, and the inhabitants of British India and the East. They may be compared to "drink" in this country, but they are important medicines.
Among the most curious and interesting facts in Nature is the extraordinary variety of the ways in which at present gutta-percha and india-rubber are employed. We should not be able to ride bicycles, or in motor-cars; we could not use Atlantic cables and many electrical apparatus; our railway carriages would be most uncomfortable; golf would be impossible; we should have no waterproof coats and no goloshes [sic], if it were not for these valuable and extraordinary substances, india-rubber or caoutchouc, and gutta-percha.
Their history is full of romance, but perhaps the most striking part of it is just this fact. Because a few (only a very few) plants found it necessary to protect their wood from burrowing beetles by a specially poisonous and elastic substance, therefore we can play golf and enjoy free-wheel bicycles.
The rubber is derived from the resinous latex or milky juice, which pours out from any wound in the bark of certain trees and creeping plants. This milk must be poisonous enough to kill the rash and intrusive mother beetle, who wishes to lay her eggs in the wood. It must be elastic, because the branches and stems swaying to and fro in the wind require a yielding, springy substance, but resin is contained in it, so that it promptly hardens and closes up the scar. The traveller Belt, in his Naturalist in Nicaragua, mentions that those trees which had been entirely drained of their rubber by the Indian gatherers were riddled by beetles, and in an unhealthy, dying condition.
Almost all the important rubber plants are found in wet, unhealthy, tropical forests; they are by far the most important jungle product in West Africa, as well as on the Congo River and in the Amazon valley.
It is quite impossible to describe the various rubber trees, and the different methods of gathering rubber, but it may be interesting to quote from an account of the method of its collection in Nicaragua, by Mr. Rowland W. Cater.136
The best season for tapping the trees of Castilloa elastica is from August to February. It is best also to perform the operation early in the morning before the daily rain, "or in the evening after the rain has fallen. The milk … is white and of the consistency of cream. The tree thrives best in moist but not marshy forests.
"It seeds in the tenth year, and ought not to be tapped before its eighth year, or its growth may be much retarded.
"On reaching the group of trees, which numbered seventeen of various sizes, my Carib friends first cut away the twining creepers that almost hid the trunks, and then carefully removed a couple of buruchas, natural ropes of rubber, formed in the following manner: From incisions in the bark, possibly caused by woodpeckers or some insect, the juice often exudes, trickling down the trunk, in and out of the encircling creepers, and sometimes reaching the ground. The milky stream coagulates and turns black as it runs, forming a long strip or cord, with which the huléros often tie up their bales.
"The parasites removed, Pete and José strapped on their espuelas (climbing spurs), fastened at the knee and ankle, and having dug a small pit or basin at the foot of each of a couple of trees, passed a ring of stout rope round the trunks and their own waists, and walked up with their machetes between their teeth. By lifting the rope at every step they were enabled to stand almost erect, and when lying back in the ring both hands were at liberty.
"José, whom I watched closely, commenced operations immediately below the first branch. With his broad-bladed sword he cut in the bark a horizontal canal which almost encircled the trunk and terminated in a V-shaped angle. From the point of the V downwards he next cut a perpendicular canal about two feet in length, which joined another horizontal channel ending in a V, and so on to the ground. In the last cut he inserted a large green leaf to serve as a funnel and guide the milk into the basin.
"The Brazilian rubber collectors always place a receptacle of tin or earthenware in the hole at the foot of the tree to prevent the admixture of grit or other foreign matters; they also strain the milk through coarse muslin; hence the greater value of Pará rubber. But Nicaraguan methods are primitive."
In the Congo Free State the taxes are paid by the collection of rubber. It is alleged that "if the demands for rubber or other produce were not satisfied, the people at fault were flogged often most barbarously with a thong of twisted hippopotamus hide, called the chicotta. Or else the natives were told to catch the women from the offending villages, who were brought to the Chef de Poste and imprisoned by him as hostages for the industry of their husbands. Or else the sentries shot some of the defaulters as examples to the rest. Frequently there were armed expeditions into refractory districts and widespread promiscuous slaughter. The cannibal soldiers of the State or of the Company sometimes feasting on the bodies of the slain."137
The supply of rubber has of recent years shown signs of becoming exhausted. As time goes on the Indians of the Amazon and Orinoco must every year travel deeper into the inaccessible forests of the Amazon, Orinoco, or in Nicaragua. Every year also makes it more difficult for the Malagasy in Madagascar, or the Negroes in West Africa and the Congo, to gather sufficient rubber for the world's ever-growing needs. Liberia, the Negro Republic, is said still to possess plenty of rubber; but it is probable that the true solution of the difficulty will be found in the plantation of rubber trees. The exports from Madagascar in 1903 were valued at 2,585,000 francs; from Brazil, £9,700,000; from Nicaragua, 400,000 gold pesos (twelve pesos to the £); from the Congo, 47,000,000 francs; but even then about 85,000 rupees worth of rubber was exported from plantations in Ceylon. Unfortunately the trees do not begin to yield until they are eight years old, but the estimated profit per acre is very high, at least according to some authorities, who give a yield of £88 per acre (in Nicaragua).
One cannot help hoping that this will be the case. When one thinks, e.g., of the Uachins in the forests at the head of Namkong, who spend forty days in carrying their rubber on men's shoulders across the mountains to Assam, or of the horrible stories of the Congo Free State, plantation seems decidedly a more satisfactory method of supplying us with golf balls and bicycle tyres.
The first account of india-rubber is found in Herrera (Columbus's second voyage), who describes the way in which the natives play "with great dexterity and nimbleness." "They struck balls with any part of their bodies."
Juan de Torquemada in 1615 gives quite a good description of the Castilloa rubber: —
"The tree is held in great estimation, and grows in a hot country. It is not a very high tree: the leaves are round and of an ashy colour: it yields a white milky substance, thick and gummy and in great abundance. It is wounded with axe or cutlass, and from the wound the liquid drops into calabashes: Indians who have got no calabashes smear their bodies over with it (for nature is never without a resource), and when it becomes dry remove the whole incrustation."138
The first patent for waterproofing seems to have been granted in 1791. A Charles Macintosh invented the garment named after him in 1823.
Very little of the commercial rubber is obtained from the common india-rubber Fig (Ficus elasticus) which we commonly grow indoors. This is one of those species of the Fig family which are generally found growing on the branches or trunks of other trees, though their own roots crawl down the trunk of the support to the ground. Once these roots have reached the ground, they take firm hold and grow so large and thick that they may be able to hold up the Fig tree even if the original support decays and crumbles away.
The gutta-percha which we use comes chiefly from Singapore, which is a sort of world's market for rubber. There are a great many different varieties and substitutes of this substance, but the best kinds come from Malaysia, Singapore, Sumatra, Java, and Borneo. The uses of gutta-percha and of vulcanite, which is manufactured from it, are very varied. Thus, it is employed for the soles of boots, door-handles, pipes, ear-trumpets, buckets, submarine cables, etc. It is indestructible in sea-water, and does not conduct electricity.
A very extraordinary exception to the general rule that latex is highly poisonous, is found in the famous Cow Tree of Venezuela. This tall tree (it is often 100 feet high) is found in large forests near Cariaco, on the coast of that country. Its milk is said to closely resemble ordinary milk in taste, and to be perfectly wholesome and nutritious, but it is rather sticky. This tree was responsible for all sorts of curious and extraordinary legends in the sixteenth and seventeenth centuries.
CHAPTER XXV
ON CLIMBING PLANTS
Robin-run-the-Hedge – Bramble bushes – Climbing roses – Spiny, wiry stems of smilax – The weak young stem of a liane – The way in which stems revolve – The hop and its little harpoons – A climbing palm – Rapidity of turners – The effect of American life on them – Living bridges – Rope bridges in India – The common stitchwort – Tendrils – Their behaviour when stroked or tickled – Their sensibility – Their grasping power – The quickness with which they curve and their sense of weight – Charles Darwin – Reasonableness of plants – Corkscrew spirals – The pads of the Virginian Creeper – The ivy – Does it do harm? – Embracing roots – Tree ivy.
THERE are many plants which depend upon and cling to other more sturdy kinds, and which would be quite unable to live upon the earth at all if they had not developed the most beautiful methods of doing so.
In autumn, as soon as the leaves of the Hawthorn have fallen off, one is sure to find upon the hedges the common Robin-run-the-Hedge (Goosegrass, Cleavers, or Sticky Willie, for it is known by all these nicknames as well as by its proper name, Galium aparine).
Its stem is exceedingly weak, but it will be found sometimes to be six or seven feet long. It does not support itself, but is resting amongst and entangled in the outer twigs of the hedge in such a manner that it cannot be blown away by the wind or indeed picked out without its being broken. The young stems grow upright and are vigorous at first, but soon they cannot bear their own weight, and fall back upon a branch of the hedge. There are small curved little roughnesses along the stem and on the under side of the leaves of the Galium; these hitch on to the twig. Up to this point then the stem is supported, and the young part above grows until it also gets a lodgment, and so it goes on until it sometimes reaches right over the top of the hedge.
Its young flowering branches grow out towards the light away from the main stem, and the yellow withered stem in autumn rests upon the hedge just as a piece of string laid upon it might do.
The Bramble and Rose manage to get a support in very much the same way, but in Great Britain the Bramble generally grows in open ground and its branches take root.
The peculiar, curved-back prickles of the Bramble and its arching sideways growth would of course hang it on to any horizontal branches in the neighbourhood. Kerner measured the length of the stem of a Bramble which had interwoven itself into the boughs of a tree, and found that it was over twenty feet long, although it was only one-third of an inch thick. In Chile one often finds hedges of Brambles ten to fifteen feet in height, which have been formed by the aid of other plants, and also by the way in which the branches become entangled with one another.
Some Climbing Roses act in a very similar way, especially if grown on trellis, but the flower shoots always turn to the light like those of the Galium.
But it is the creepers and lianes of the tropical forests that are the most remarkable of all climbing plants. They twine round the stems and hang in great loops and grotesque folds from the branches. Sometimes in the dense shade it may be difficult to see the main stem, for it is quite thin, though as strong as a piece of steel wire. It often happens, when hurrying through a rather open part of the forest after game, that one's leg suddenly catches in a thin, spiny, wiry stem of Smilax or some such creeper. The first that one knows of the creeper is when a quarter of an inch of the spine is buried in one's flesh.
Away up amongst the branches and foliage far above one's head, leaves and flowers are developed on numerous branches which have vigorously pushed out as soon as they got near the sunlight, this tough, spiny, thread-like stem being their only connexion with the ground.
The development of these climbing plants is probably connected with the dense shade of forests. In such places a young stem growing up will become long and drawn out; its tip will droop over and hang downwards. But there is a curious peculiarity in the growth of all stems. The stem generally grows more rapidly at any one time on one side, say on the north, and therefore bends over to the opposite side. After a time it will be growing most rapidly on the eastern side and then its head points westwards, and so on. The result is that the tip of the stem swings in an irregular circle round the stem itself. Its head turns to every point of the compass in succession. Supposing a stone is tied to the end of a piece of string, and one swings the stone horizontally in a circle, then, if an upright stick is put in the ground and the string comes against it, the string will coil itself round the stick because the stone goes on swinging horizontally.
Our young climbing plant in the shade of the forest acts in exactly the same way. If there is any trunk of a suitable size, it will in the course of its revolving or sweeping round first touch and then coil itself round and round the trunk.139 Of these twining stems, one of the most interesting and beautiful is the common Hop. The young shoots or suckers which come from the ground may be seen waving their stems helplessly round in the air. If they cannot find something to cling to, then they form weak limp curves, but if one such shoot touches a pole it very soon obtains a hold, wraps itself round the support, and easily climbs up to a height of many feet. But the Hop is worth examining closely. If one passes the fingers along the stem, it feels rough and prickly. With the aid of a hand-lens, a whole series of most exquisite little hooks will be discovered. They are like small pimples with two or three very fine and minute, sharp grappling-hooks on the top. These prevent the stem from slipping off. It is also helped in climbing by its leaves, which curve outwards, and are also provided with grappling prickles on the under side. At the top of the stem the young leaves are close together, and folded near the point, so as not to interfere with the tip finding its way in and out of a trellis-work or amongst branches.
These grappling-hooks on the Hop are as perfect in their way, though by no means so beautiful and elegant as those which are found in the climbing palm, Desmoncus, so well described by Kerner in his Natural History of Plants. It is one of the rotang palms which reach lengths of 600 feet, though their stem may be no more than 1-1/3 to 2 inches thick. The leaflets towards the end of the leaf are transformed into strong spiny barbs which are exquisitely adapted to hang on to other plants. In many places, thickets in which these rotang palms have developed are so matted and tangled together that it is quite impossible even to cut into them, and they are practically impenetrable.
Some of our common British twiners climb very quickly. A complete turn round the supporting pole was made in England, at Charles Darwin's home, in the following times. The Hop took 2 hrs. 8 mins., Wistaria 2 hrs. 5 mins., Convolvulus 1 hr. 42 mins., and Phaseolus 1 hr. 54 mins. A Honeysuckle took 7 hrs. 30 mins. to make one complete turn round the support.
Recently Miss Elizabeth A. Simons timed the rate of growth of the same plants at the University of Pennsylvania. They seem to have been stimulated by the exhilarating atmosphere of the United States, for they were all growing faster. The Hop did its turn in 1 hr. 5 mins., Phaseolus took from 1 hr. to 1 hr. 20 mins., Convolvulus 57 mins. only, Lonicera from 1 hr. 43 mins. to 2 hrs. 48 mins., and Wistaria 2 hrs.140 But there are curious variations in the rate at which these plants revolve.
Thus when coming towards the light they go as fast as they can, but revolve more slowly, and as it were reluctantly, away from it. It has been found in one case that the shoot took thirty-five minutes to do the semicircle towards the light, and an hour and fifteen to twenty minutes going away from it, but this is not always the case, for sometimes the reverse takes place141 (Baranetzki).
These twining plants are not very common in Great Britain, and indeed in Europe. Some of them move or twine to the right (in the same direction as the hands of a watch or of the sun), such as Convolvulus (Bindweed), Phaseolus, Ipomœa, and Aristolochia. Others, like the Hop, Polygonum, Convolvulus, Honeysuckle, and Elephant's Foot, move in the opposite way from right to left, or "widder-shins." But there is nothing very important in this distinction, for the Bittersweet may be found twining in either direction, and in some plants part of a stem may be twining one way and the other in the opposite direction.
It is in the tropics, and especially in the rank, dark, moisture-laden atmosphere of the coast jungle forests, that these twiners attain their greatest development.
They show the most extraordinary variety. Sometimes a twiner hangs in elegant festoons from branch to branch, forming a convenient suspension bridge for monkeys. Sometimes four or five are wound round one another or twisted together, so that they look like some gigantic cable. In other cases they are knotted, looped, tangled, and twisted in the most inextricable manner.
Some creepers are flat, like green ribbons or broad bands. In others the dense mass of old, thick creepers and twiners round some sturdy trunk becomes so thick and so fused together that when the trunk dies the lattice-like arrangement of these creepers may keep them upright although the original supporting trunk is quite rotten and decayed away.
More usually, a tree will become unhealthy because its branches are overladen with the dense foliage and flowers of heavy lianes, and because both trunk and branches are so strangled in the embrace of great creepers that they cannot expand and develop in the proper way. Then a storm will overthrow the dead giant of the forest, and these creepers, entangled with all the surrounding trees, will produce ruin and destruction all around.
A regular duty of the foresters in India is to cut the stems of climbing plants. These twining, trailing, rope-like creepers are, in fact, natural ropes, and are used as such in India, Burma, and other places. Sometimes they form natural bridges of living plants extending across a stream. The great suspension bridges in the valleys of the Himalayas are sometimes made without a single nail or plank. They are just three ropes (one for the feet and two to hold on by) made of jungle creepers. Crossing one of these swinging, swaying creeper-bridges is not an easy matter for those whose heads are unaccustomed to depths of hundreds of feet below them, especially if combined with a motion of the creeper-bridge sufficient in itself to produce violent seasickness. Yet the natives run across them with loads on their heads!
