APPENDIX A
Notes on the Geography and Meteorology of Mashonaland
By Robert M. W. Swan, Esq.
Central Mashonaland consists of elevated granite plateaux, varying in height between 3,000 and 5,000 feet. Through the surface of these plains rise groups of isolated little granite hills which are most remarkable and varied in form, and which sometimes attain an elevation of 1,000 feet above their base, but more frequently they are about 400 feet high. Generally they are composed of enormous broken blocks of granite, but often they are dome-shaped and of one unbroken mass of rock, and suggest the idea of huge bubbles on the surface of a molten mass. The summits of the latter kind of hills are, of course, quite inaccessible. They are not hills left in relief by the denudation of the surrounding country, but, judging from exposed sections of some that I have seen, they have been elevated by a force acting at a comparatively small distance below the present surface, and they are older than the stratified rocks of the country.
On the granite plateaux one meets with patches of stratified rock—of quartzites and schists, and rarely some crystalline limestone. Magnesia, too, is sometimes present, [[390]]notably at Umtali, and in the steatite which occurs near the Great Zimbabwe, of which many of the objects found in the excavations were made. The strike of the strata is generally east and west, and the various patches arrange themselves in several fairly continuous lines running across the country in the same direction as the strike. These semi-continuous deposits or belts of stratified rock are generally two or three miles wide, and in them occur the gold-bearing quartz reefs. The most southerly belt that I know of in Mashonaland proper passes by Fort Victoria, and probably crosses the Sabi River about latitude 20°. The next large one passes by Umtali and the ’Mfuli River, where it crosses the waggon-road, and so on to Hartley Hill. This belt includes Mount Wedsa, the highest mountain in Mashonaland. Next in order comes the Mazoe deposit, which perhaps also includes the Kaiser Wilhelm gold-field. These deposits are all fairly similar in nature, but no fossils have been found in them, and their age has not been determined. They probably represent a continuous sheet of stratified rock, all of which has been denuded away except the above-mentioned belts. They generally present a rugged surface, elevated in mountain ranges, which often rise 1,500 and 2,000 feet above their base, and, although they are nearly always steep, they are rarely precipitous. These mountains are regular and beautiful in outline, and refresh the eye after it has grown wearied of the grotesque forms of the granite hills. The soil on the stratified rocks is more fertile than it is on the granite, and the vegetation is more charming; the very coarse grasses of the granite soils being replaced by many flowering plants.
The ruins which have just been described are all built on granite, but are generally within a short distance of the quartz formation; and the ruins at Zimbabwe are situated four miles from the southern edge of the quartz belt. At Zimbabwe we found little clay crucibles in which gold had been melted, [[391]]and an accumulation of quartzite rock which had been obtained from the casing of a quartz reef. I carefully tested this rock for gold, but could only find a very minute trace; so I conclude that it had been rejected as too poor for treatment. While at Zimbabwe, whenever I could spare time from the excavations, I made excursions to the quartz belt, and searched for old workings and gold reefs. I found one reef carrying a small quantity of gold, but no old workings. Since then, however, rich gold reefs have been discovered about twenty miles to the north-west of Zimbabwe, and from these probably the ancients obtained their quartz. The quartz formation near the little ruin at the Mazoe River has been much worked for gold, and the Manica belt seems to have been even more exploited. Where the high plateau breaks down at Massi-Kessi an enormous amount of alluvial has been worked. The old people must have obtained, from both the alluvial and the reefs, a great quantity of gold to repay them for the work that they did, and there is no reason to suppose that they have exhausted the reefs; indeed, I have seen at the bottom of old workings the reef continuing and carrying visible gold.
Besides gold reefs, these quartz belts contain much iron ore and some manganese. In two isolated patches of the quartzite formation at the Doroba Mountains, near the Sabi River, I found great masses of rich magnetite and hematite, and on the top of Mount ’Nyaguzwe, near Fort Victoria, there is also a mass of magnetite; in fact, so very abundant is iron ore, that compass bearings can rarely be taken with safety from hills in the quartz formation. Along the right bank of the Sabi River, near Mount Wedsa, are many native villages, whose one industry is iron smelting. They obtain the ore from Mount Wedsa, which is renowned far and wide in Kaffirland as an iron-producing mountain. The mineral they select is not very rich, and is consequently more easily [[392]]smelted, and it contains some manganese. The iron they produce is very pure, and is consequently soft and easily fashioned into weapons and tools. Their anvils are simple blocks of hard diorite, on which they hammer with another smaller block.
The tributaries of the Sabi River flowing near Zimbabwe have been ill-defined on previous maps. The ’Mpopotekwe joins the ’Mtelekwe and the ’Mshagashe flows into the united stream a short distance south of Zimbabwe. This river, under the name of the ’Mtelekwe, then flows into the Lunde, and not to the Sabi direct. The Tokwe joins the Lunde farther north. The most interesting geographical work that we did was on our expedition to the Sabi River, and on that from Fort Salisbury to ’Mtoko’s, and down by Mangwendi’s and Makoni’s country to Umtali. On our journey to the Sabi we crossed a great many of its western tributaries; and as the same streams rose near the waggon-road, and we crossed them pretty far down their courses, we were able to lay down their direction for a considerable distance with certainty. The Sabi River itself, in latitude 19° 15′, we found was placed twenty miles too far west in former maps; and from the information which I gathered from the natives, in the latitude of Zimbabwe, it must be about fifty miles farther east than it is placed in these maps. This river, where we struck it, was a considerable stream flowing rapidly over a rocky bed. It had fallen about 1,800 feet from its source near Fort Charter, and had 2,700 feet more to fall before it reached the sea. When it has received all the tributaries we crossed it must be a very big river.
Going from Fort Salisbury to ’Mtoko’s we crossed many tributaries of the Mazoe River, which were either not shown at all in former maps, or were most inaccurately placed. We recrossed these streams again farther up returning from ’Mtoko’s to Mangwendi’s. I also got excellent views of them [[393]]from the various mountains which I ascended, so that I was able to lay them down in my map with certainty. To the eastward of ’Mtoko’s we could see the high veldt breaking into mountain ranges as it descended towards Gouveia’s country.
Approaching Mangwendi’s, and also going between Mangwendi’s and Chipunza’s, our way lay along a very high watershed, on the western side of which rose some of the eastern tributaries of the Sabi River, the most important of which was the ’Msheke. At Makoni’s we reached the highest part of the plateau, and this is, with the exception of some villages on Mount Yenya, the highest inhabited part of Mashonaland. From Makoni’s to Mount Yenya the country is broken; and the descent is very rapid, but on the east of our route the descent is still more rapid and the mountains more imposing. On the north side of Mount Yenya flows the Odzi River, which is there a very considerable stream. Mount Yenya is a most imposing mountain and the highest in Mashonaland, with the exception of Mount Wedsa. It rises to a height of 5,800 feet above sea level, and within 300 feet of its summit are several villages which own a considerable number of cattle. It probably represents the Mount Doe which the Portuguese place on their maps about this part, and which they say is 7,900 feet high, for certainly there is no mountain near Mount Yenya of equal height. Between Umtali and Massi-Kessi the country is extremely mountainous, and the scenery is the grandest that we saw in Mashonaland. We lost 1,400 feet in height between these two places. A short distance after leaving Massi-Kessi we crossed the Revwe River, and our way lay along a watershed about 2,000 feet high. This watershed is thickly wooded, and is traversed sometimes by deep ravines. On the left hand the streams flow to the Pungwe River, and on the right to the Revwe and the Muda and Mutuchiri Rivers. [[394]]Approaching Sarmento, the country falls rapidly to nearly sea level; and thence to the coast we traversed a flat alluvial country through which the Pungwe River sluggishly flows. This swampy level country swarms with game, especially towards the end of the dry season, but the vegetation is not nearly so luxuriant as one would expect, and some parts of this country are quite bare.