tropical plants used for industrial purposes.
cotton—its cultivation in the united states—caoutchouc and gutta percha—manner in which these resins are collected—indigo—the british logwood cutters in honduras—brazil wood—arnatto.
under the plantagenets and the tudors, wool formed the chief export of england. the pastoral races that inhabited the british isles, unskilled in weaving, suffered the more industrious flemings to convert their fleeces into tissues; and the dominions of the duke of burgundy, enriched by manufactures and by the stimulus they gave to agriculture, became the most prosperous part of europe. at length the islanders began to discover the sources of the wealth which rendered ghent and bruges, ypres and louvain, the marvel and envy of the mediæval world; and gradually learning to keep their wool at home, invited the flemings to the shores of england.
the bigoted oppression of spain came in aid of this more enlightened policy: our wool ceased to be sent abroad, and english cloth eventually became the chief of our exports. but, like all human affairs, trade is subject to eternal fluctuation, new wants are constantly created, new markets opened, new articles introduced, and thus, almost within the memory of living man, the wool-manufactory has ceased to be the great staple of our189 industry; and, thanks to the inventive genius of our arkwrights and cromptons, a vegetable fibre furnished by a plant totally unknown to our forefathers, now ranks as the first of all the world-wide importations of england.
there are many different species of the cotton-plant, herbaceous, shrubby, and arboreal. their original birthplace is the tropical zone, where they are found growing wild in all parts of the world; but the herbaceous species still thrive under a mean temperature of from 60° to 64° f., and are capable of being cultivated with advantage as far as 40° or even 46° n. lat. the five-lobed leaves have a dark green colour, the flowers are yellow with a purple centre, and produce a pod about the size of a walnut, which, when ripe, bursts and exhibits to view the fleecy cotton in which the seeds are securely embedded.
it is almost superfluous to mention that the united states is the first cotton-producing country in the world. the area suitable for cotton south of the thirty-sixth degree of latitude, comprises more than 39,000,000 acres, of which less than one-sixth part is now devoted to the plant. the yield depends in part upon the length of the season. seven months are required for an average crop, and the average periods in which the last killing frost of spring and the first killing frost of autumn occur are march 23, and october 26. cotton is cultivated in large fields, and when the soil is superior, the plant rises to a height of six or eight feet, although in the richest cane-brake soil, exhausted by successive crops, it dwindles down to a height of three or four feet only. the aspect of a cotton field is most pleasing in the autumn, when the dark-coloured foliage and bright yellow flowers, intermingling with the snow-white down of the pods when burst, produce a charming contrast. at that time all hands are at work, for it is important to pluck as much as possible during the first hours of morning, since the heat of the sun injures the colour of the cotton, and the over-ripe capsules shed their contents upon the ground, or allow the wind to carry them away.
the collected produce is immediately carried to the steam-mill to be cleansed of the seeds, and then closely packed in bales, which in the seaports are further reduced by hydraulic presses to half of their previous volume, thus causing a great saving in the freight. large clippers frequently carry eight or ten190 thousand of these bales to liverpool, whence, perhaps on the day of their arrival, they are conveyed by rail to the next manufacturing town, which returns them in a few days to the port, ready to clothe the australian gold-digger or the labourer on the banks of the ganges.
india, which still in the last century provided europe with the finest cambrics and muslins, now yearly receives from england cotton goods to a large amount. thus the stream of trade may be said to have rolled backwards to its source, for though the wants of the hindoo are easily satisfied, and cotton grows at his very door, yet his hand-loom is unable to compete with the machinery and the capital of england. even in the exportation of the raw material he labours under great disadvantage when compared with america, though railroads and a better system of culture have done much to improve the quality and facilitate the transport of indian cotton.
when we consider the luxuriance of vegetation in the tropical zone, it is not to be wondered at that so many plants of those climes abound with juices of a variety and richness unknown to those of the temperate latitudes. the resins and gums which our indigenous trees produce, either in smaller quantities or fit only for common uses, are there endowed with higher virtues, and ennobled, as it were, by the rays of a more powerful sun. sometimes they exude spontaneously through the rind and harden in the atmosphere; more frequently a slight incision is required to make the sap gush forth in which they are dissolved, but in every case they require but trifling labour for their collection. many of them have medicinal qualities, others are esteemed for their aromatic odour, but none ranks higher in a commercial and technical point of view than caoutchouc or india-rubber, which was first brought from south america to europe as a great curiosity at the beginning of the last century, and is now absolutely indispensable for a thousand different uses. nothing was known even of its origin until the year 1736, when the french naturalist la condamine, while exploring the banks of the amazon, discovered that it was chiefly produced by the siphonia elastica, a large tree growing wild in the primitive forests along the borders of the rivers in guiana and north brazil.
the resin is collected by the indians in a very simple191 manner. with a small hatchet they make deep and long incisions in the rind, from which a milky sap abundantly exudes. a small wooden peg is then fixed into each aperture to prevent its closing, and a cup of moist clay fastened underneath, which in about four or five hours is filled with as many table-spoonfuls of the juice. the produce of a number of incisions having been gathered in a large earthen vessel, is then spread in thin coatings upon moulds made of clay, and dried, layer after layer, over a fire, until the whole has acquired a certain thickness. when perfectly dry, the clay form within is broken into small fragments, and the pieces are extracted through an aperture, which is always left for the purpose.
besides the siphonia elastica, many other american trees, belonging to the families of the euphorbiaceæ and urticeæ, afford excellent kinds of caoutchouc; and since it is become so valuable an article of commerce, the east indies, and java likewise, yield considerable quantities, chiefly from the urceola elastica and the ficus elastica.
the icosandra gutta, which furnishes the gutta percha of commerce, is a native of the eastern archipelago and the adjacent lands. a few years since, this substance, now so celebrated and of such wide extended use, was totally unknown in europe, for though from time immemorial the malays employed it for making the handles of their hatchets and creeses, it was only in the year 1843 that mr. montgomery, an english surgeon, having casually become acquainted with its valuable properties, sent an account of it, with samples, to the royal society, for which he was most justly rewarded with its gold medal. the fame of the new article spread rapidly throughout the world; science and speculation seized upon it with equal eagerness; a thousand newspapers promulgated its praises; it was immediately analysed, studied, and tried in every possible way, so that it is now as well known and as extensively used as if it had been in our possession for centuries.
the icosandra gutta is a large high tree, with a dense crown of rather small dark green leaves, and a round smooth trunk. the white blossoms change into a sweet fruit, containing an oily substance fit for culinary use. the wood is soft, spongy, and contains longitudinal cavities filled with brown stripes of gutta percha. the original method of the malays for collecting192 the resin consisted in felling the tree, which was then placed in a slanting position, so as to enable the exuding fluid to be collected in banana leaves. this barbarous proceeding, which from the enormous demand which suddenly arose for the gutta would soon have brought the rapidly rising trade to a suicidal end, fortunately became known before it was too late, and the resin is now gathered in the same manner as caoutchouc, by making incisions in the bark with a chopping knife, collecting the thin, white, milky fluid which exudes in large vessels, and allowing it to evaporate in the sun or over a fire. the solid residuum, which is the gutta percha of commerce, is finally softened in hot water, and pressed into the form of slabs.
grutta percha has many properties in common with caoutchouc, being completely insoluble in water, tenacious, but not elastic, and an extremely bad conductor of caloric and electricity. the name of vegetable leather which has been applied to it, gives a good idea both of its appearance and tenacity.
its uses are manifold. it serves for water-pipes, for vessels fit for the reception of alkaline or acid liquids which would corrode metal or wood, for surgical implements, for boxes, baskets, combs, and a variety of other articles. the wonder of the age, submarine telegraphy, could hardly have been realised without it, as it is only by being cased in so isolating a substance, and one so impermeable by water, that the metallic wire is able to transmit the galvanic stream through the depths of ocean from land to land.
of all the dyeing substances which the tropical zone produces in such endless variety, none is more important in a commercial point of view than indigo. various species of plants producing this beautiful cerulean colour are found growing spontaneously in the warmer countries of both hemispheres, but the indigofera tinctoria is most generally cultivated. the knotty shrubby plant rises about two feet from the ground; the leaves are winged like those of the acacia, smooth and soft to the touch, furrowed above, and of a darker colour on the upper than the under side. the small reddish flowers which grow in ears from the axillæ of the leaves have no smell, and are succeeded by long crooked brown pods, which contain small yellow seeds. the plant requires a smooth rich soil, well tilled, and neither too dry nor too moist. a child of the sun, it cannot be193 advantageously cultivated anywhere except within the tropics, a higher mean temperature than 60° being absolutely necessary for its vegetation. the seed is sown in furrows a foot apart from each other, and two or three inches in depth. sufficient moisture causes it to shoot above the surface in three or four days, and it is usually fit for gathering at the end of two months. when it begins to flower it is cut with a sickle a few inches above the roots, and furnishes, after six or eight weeks, a second crop. the cultivation of indigo would thus seem to be extremely profitable, but the sun, which so rapidly improves and invigorates the plant, calls forth at the same time a multitude of insects and caterpillars, that prey upon the valuable leaves, and frequently disappoint the planter’s expectations.
cutting the indigo plant.
all the intermediate shades of violet and purple may be obtained from the mixture of red and blue, varying according to the different proportions wherein these colours are applied. there are, however, some few vegetable substances which yield a violet or purple dye, without being combined with another colour, and of these logwood is the most important. the stately tree which furnishes this valuable article of commerce is a native of the western world, having been first discovered in194 the swampy forests of yucatan, and in the low alluvial grounds that girdle the bays of campeachy and honduras.
about the year 1661, logwood became in great request; and as the indolent spaniards to whom the country at that time belonged failed to supply the market, several english adventurers, without first asking permission, settled or squatted on the uninhabited coast of yucatan, and made the woods near laguna de terminos ring with the sound of their industrious axe. many years passed without the spaniards taking any notice of the intruders; but as these, growing bolder by sufferance, began to penetrate farther into the country, to build houses and form plantations, as if they had been masters of the soil, their jealousy was at length aroused, and in 1680 the english settlers were forcibly ejected. this triumph on the part of their adversaries was, however, but transitory; and a few months after our sturdy countrymen were again cutting their logwood as busily as ever, in spite of the enmity of man and the innumerable hardships of their laborious occupation.
their mode of life is thus quaintly described by dampier in his voyage to the bay of campeachy:—‘the logwood-cutters inhabit the creeks of the lagunes in small companies, building their huts by the creeks’ sides for the benefit of the sea-breeze, as near the logwood groves as they can, and often removing to be near their business. though they build their huts but slightly, yet they take care to thatch them very well with palmetto leaves, to prevent the rains, which are there very violent, from soaking in. for their bedding, they raise a wooden frame, three feet and a half above ground on one side of the house, and stick up four stakes at each corner, to fasten their curtains, out of which there is no sleeping for mosquitoes. another frame they raise, covered with earth, for a hearth, to dress their victuals; and a third to sit at, when they eat it. during the wet season, the land where the logwood grows is so overflowed that they step from their beds into the water, perhaps two feet deep, and continue standing in the wet all day till they go to bed again; but, nevertheless, account it the best season for doing a good day’s labour in. some fell the trees, others saw and cut them into convenient logs, and one chips off the bark, and he is commonly the principal man; and when a tree is so thick that after it is logged it195 remains still too great a burden for one man, it is blown up with gunpowder. the logwood-cutters are generally sturdy strong fellows, and will carry burthens of three or four hundredweight. in some places they go a-hunting wild cattle every saturday to provide themselves with beef for the week following. when they have killed a beef they cut it into quarters, and taking out the bones, each man makes a hole in the middle of his quarter, just big enough for his head to go through, then puts it on like a frock and trudgeth home; and, if he chanceth to tire, he cuts off some of it and throws it away.’
the entire freedom from all restraint which accompanied this wild and adventurous life had such charms for dampier’s bold and roving spirit, that he sojourned for about a year among the rude wood-cutters of campeachy, and left them with the intention of again returning for a longer stay.
most of the red dye-woods are furnished by the cæsalpinias, a genus of plants belonging to the widespread family of the leguminosæ, and indigenous in both hemispheres. the c. crista, which furnishes the best quality, commonly known under the name of brazil wood, grows profusely in the forests of that vast empire, preferring dry places and a rocky ground. its trunk is large, crooked, and full of knots; at a short distance from the ground innumerable branches spring forth and extend in every direction in a straggling manner. the branches are armed with short strong upright thorns, the leaves are small, and never appear in luxuriant foliage. the flowers are of a beautiful red colour, and emit a fragrant smell. both the thick bark and the white pithy part of the trunk are useless, the hard close-grained heart being the only portion impregnated with colouring matter. the wood is sometimes used in turning, and is susceptible of a good polish, but its chief use is as a red dye. by the addition of acids it produces a permanent orange or yellow colour, while the crimson tints which it imparts are very fleeting.
the first europeans that settled on the banks of the amazons found that several of the indian tribes that roamed about in their vicinity painted their bodies with a showy orange-red colour. their attention was by this means attracted to the arnatto (bixa orellana), which attains about the size of our196 hazel-tree. the heart-shaped leaves are about four inches long, of a lighter green on the upper surface, and divided by fibres of a reddish-brown colour; the rosy flowers are succeeded by bristled pods somewhat resembling those of a chestnut, which, bursting open when ripe, display a splendid crimson farina or pulp, in which are contained thirty or forty seeds, in shape similar to raisin stones. as soon as they have arrived at maturity the pods are gathered, divested of their husks, bruised, immersed in water, and after a few weeks beaten with sticks to promote the separation of the pulp from the seeds. the turbid liquor is then strained, boiled to a consistent paste, and finally formed into cakes, which are left to dry in the sun. in england arnatto is generally used by the dyer to give a deeper shade to the simple yellow. being perfectly soluble in spirits of wine, it is much used in this state for lacquering and for giving an orange tint to the yellow varnishes. it is likewise employed in large quantities as a colouring ingredient for cheese, to which it gives the required tinge without imparting any unpleasant flavour or unwholesome quality.
