The reader is warned that amongst the East Africans the “bay o shara”—barter or round trade—is an extensive subject, of which only the broad outlines and general indications can be traced. At present, the worthlessness of time enables both buyer and seller to haggle ad libitum, and the superior craft of the Arab, the Banyan, the Msawahili, and the more civilised slave, has encumbered with a host of difficulties the simplest transactions. It is easy to be a merchant and to buy wholesale at Zanzibar, but a lengthened period of linguistic study and of conversancy with the habits and customs of the people must be spent by the stranger who would engage in the task of retail-buying in the interior.
The principal article of export from the Zanzibar coast is copal, from the interior ivory. The minor items are hippopotamus teeth, rhinoceros horns, cattle, skins, hides, and horns, the cereals, timbers, and cowries. Concerning the slaves, who in East Africa still form a considerable item of export, details have been given in the preceding pages. The articles which might be exploited, were means of carriage supplied to the people, are wax and honey, orchella-weed, fibrous substances, and a variety of gums.
The copal of Zanzibar, which differs materially from that of the Western Coast of Mexico and the cowaee (Australian dammar?) of New Zealand, is the only article convertible into the fine varnishes now so extensively used throughout the civilised world.
As the attention of the Expedition was particularly directed to the supplies of copal in East Africa by Dr. G. Buist, LL.D., Secretary to the Bombay branch of the R. G. Society, many inquiries and visits to the copal diggings were made. In the early part of 1857 specimens of the soils and subsoils, and of the tree itself, were forwarded to the Society.
The copal-tree is called by the Arabs shajar el sandarús, from the Hindostani chhandarus; by the Wasawahili msandarusi; and by the Wazaramo and other maritime races mnángú. The tree still lingers on the island and the mainland of Zanzibar. It was observed at Mombasah, Saadani, Muhonyera, and Mzegera of Uzaramo; and was heard of at Bagamoyo, Mbuamaji, and Kilwa. It is by no means, as some have supposed, a shrubby thorn; its towering bole has formed canoes 60 feet long, and a single tree has sufficed for the kelson of a brig. The average size, however, is about half that height, with from 3 to 6 feet girth near the ground; the bark is smooth, the lower branches are often within reach of a man’s hand, and the tree frequently emerges from a natural ring-fence of dense vegetation. The trunk is of a yellow-whitish tinge, rendering the tree conspicuous amid the dark African jungle-growths; it is dotted with exudations of raw gum, which is found scattered in bits about the base; and it is infested by ants, especially by a long ginger-coloured and semi-transparent variety, called by the people maji-m’oto, or “boiling water,” from its fiery bite. The copal wood is yellow tinted, and the saw collects from it large flakes; when dried and polished it darkens to a honey-brown, and, being well veined, it is used for the panels of doors. The small and pliable branches, freshly cut, form favourite “bakur,” the kurbaj or bastinadoing instrument of these regions; after long keeping they become brittle. The modern habitat of the tree is the alluvial sea-plain and the anciently raised beach: though extending over the crest of the latter formation, it ceases to be found at any distance beyond the landward counterslope, and it is unknown in the interior.
The gum copal is called by the Arabs and Hindus sandarus, by the Wasawahili sandarusi, and by the Wanyamwezi—who employ it like the people of Mexico and Yucatan as incense in incantations and medicinings—sirokko and mámnángu. This semi-fossil is not “washed out by streams and torrents,” but “crowed” or dug up by the coast clans and the barbarians of the maritime region. In places it is found when sinking piles for huts, and at times it is picked up in spots overflowed by the high tides. The East African seaboard, from Ras Gomani in S. lat. 3° to Ras Delgado in 10° 41′, with a medium depth of 30 miles, may indeed be called the “copal coast;” every part supplies more or less the gum of commerce. Even a section of this line, from the mouth of the Pangani River to Ngao (Monghou), would, if properly exploited, suffice to supply all our present wants.
The Arabs and Africans divide the gum into two different kinds. The raw copal (copal vert of the French market) is called sandarusi za miti, “tree copal,” or chakází, corrupted by the Zanzibar merchant to “jackass” copal. This chakazi is either picked from the tree or is found, as in the island of Zanzibar, shallowly imbedded in the loose soil, where it has not remained long enough to attain the phase of bitumenisation. To the eye it is smoky or clouded inside, it feels soft, it becomes like putty when exposed to the action of alcohol, and it viscidises in the solution used for washing the true copal. Little valued in European technology, it is exported to Bombay, where it is converted into an inferior varnish for carriages and palanquins, and to China, where the people have discovered, it is said, for utilising it, a process which, like the manufacture of rice paper and of Indian ink, they keep secret. The price of chakazi varies from 4 to 9 dollars per frasilah.
The true or ripe copal, properly called sandarusi, is the produce of vast extinct forests, overthrown in former ages either by some violent action of the elements, or exuded from the roots of the tree by an abnormal action which exhausted and destroyed it. The gum, buried at depths beyond atmospheric influence, has, like amber and similar gum-resins, been bitumenised in all its purity, the volatile principles being fixed by moisture and by the exclusion of external air. That it is the produce of a tree is proved by the discovery of pieces of gum embedded in a touchwood which crumbles under the fingers; the “goose-skin,” which is the impress of sand or gravel, shows that it was buried in a soft state; and the bees, flies, gnats, and other insects which are sometimes found in it delicately preserved, seem to disprove a remote geologic antiquity. At the end of the rains it is usually carried ungarbled to Zanzibar. When garbled upon the coast it acquires an additional value of 1 dollar per frasilah. The Banyan embarks it on board his own boat, or pays a freight varying from 2 to 4 annas, and the ushur or government tax is 6 annas per frasilah with half an anna for charity. About 8 annas per frasilah are deducted for “tare and tret.” At Zanzibar, after being sifted and freed from heterogeneous matter, it is sent by the Banyan retailer to the Indian market or sold to the foreign merchant. It is then washed in solutions of various strengths: the lye is supposed to be composed of soda and other agents for softening the water; its proportions, however, are kept a profound secret. European technologists have, it is said, vainly proposed theoretical methods for the delicate part of the operation which is to clear the goose-skin of dirt. The Americans exported the gum uncleaned, because the operation is better performed at Salem. Of late years they have begun to prepare it at Zanzibar, like the Hamburg traders. When taken from the solution, in which from 20 to 37 per cent. is lost, the gum is washed, sun-dried for some hours, and cleaned with a hard brush, which must not, however, injure the goose skin; the dark “eyes,” where the dirt has sunk deep, are also picked out with an iron tool. It is then carefully garbled with due regard to colour and size. There are many tints and peculiarities known only to those whose interests compel them to study and to observe copal, which, like cotton and Cashmere shawls, requires years of experience. As a rule, the clear and semi-transparent are the best; then follow the numerous and almost imperceptible varieties of dull white, lemon colour, amber yellow, rhubarb yellow, bright red, and dull red. Some specimens of this vegetable fossil appear by their dirty and blackened hue to have been subjected to the influence of fire; others again are remarkable for a tender grass-green colour. According to some authorities, the gum, when long kept, has been observed to change its tinge. The sizes are fine, medium, and large, with many subdivisions; the pieces vary from the dimensions of small pebbles to 2 or 3 ounces; they have been known to weigh 5 lbs., and, it is said, at Salem a piece of 35 lbs. is shown. Lastly, the gum is thrown broadcast into boxes and exported from the island. The Hamburg merchants keep European coopers, who put together the cases whose material is sent out to them. It is almost impossible to average the export of copal from Zanzibar. According to the late Lieutenant-Colonel Hamerton, it varies from 800,000 to 1,200,000 lbs. per annum, of which Hamburg absorbs 150,000 lbs., and Bombay two lacs’ worth. The refuse copal used formerly to reach India as “packing,” being deemed of no value in commerce; of late years the scarcity of the supply has rendered merchants more careful. The price, also, is subject to incessant fluctuations, and during the last few years it has increased from 4 dol. 50 cents to a maximum of 12 dollars per frasilah.
According to the Arabs, the redder the soil the better is the copal. The superficies of the copal country is generally a thin coat of white sand, covering a dark and fertilising humus, the vestiges of decayed vegetation, which varies from a few inches to a foot and a half in depth. In the island of Zanzibar, which produces only the chakazi or raw copal, the subsoil is a stiff blue clay, the raised sea-beach, and the ancient habitat of the coco. It becomes greasy and adhesive, clogging the hoe in its lower bed; where it is dotted with blood-coloured fragments of ochreish earth, proving the presence of oxidising and chalybeate efficients, and with a fibrous light-red matter, apparently decayed coco-roots. At a depth of from 2 to 3 feet water oozes from the greasy walls of the pit. When digging through these formations, the gum copal occurs in the vegetable soil overlying the clayey subsoil.
A visit to the little port of Saadani afforded different results. After crossing 3 miles of alluvial and maritime plain, covered with a rank vegetation of spear grass and low thorns, with occasional mimosas and tall hyphænas, which have supplanted the coco, the traveller finds a few scattered specimens of the living tree and pits dotting the ground. The diggers, however, generally advance another mile to a distinctly formed sea-beach, marked with lateral bands of quartzose and water-rolled pebbles, and swelling gradually to 150 feet from the alluvial plain. The thin but rich vegetable covering supports a luxuriant thicket, the subsoil is red and sandy, and the colour darkens as the excavation deepens. After 3 feet, fibrous matter appears, and below this copal, dusty and comminuted, is blended with the red ochreish earth. The guides assert that they have never hit upon the subsoil of blue clay, but they never dig lower than a man’s waist, and the pits are seldom more than 2 feet in depth. Though the soil is red, the copal of Saadani is not highly prized, being of a dull white colour; it is usually designated as “chakazi.”