Throughout the tropics the harmless kinds of lizards may invariably be reckoned amongst the settlers in every house. Prettily marked skinks (Euprepes quinquelineatus and E. pleurostictus) enlivened my abode, whilst the graceful gecko (Hemidactylus verrucalutus) clambered up and down the walls just as frequently as in Egypt and in Nubia. But more numerous than all were the sociable agamæ (Agama colonorum), which kept nodding their heads, in a way that was extremely irritating to the Mohammedans, who fancied that it was the devil making fun of their prayers. I had previously repeatedly seen this species of the lizard in the overhanging rocky crags of the desert valleys on the Egyptian coast of the Red Sea; but here it appeared to lodge itself quite as freely in the huts as in the woods. The head of the male is of an orange-colour, and is easily detected from a considerable distance. Very ridiculous are their movements when any one approaches a tree upon which they are running up and down. They betake themselves to the farther side of the stem, and keep stopping at intervals, peeping out cunningly first from one branch and then from another, their large eyes beaming with a most knowing expression. Their favourite resort, however, in this district was the old woodwork of the palisades, and there they mustered in thousands.
I was very much surprised, at the beginning of the rainy season, at the large number of chameleons which at intervals clustered themselves upon the sprouting foliage. The common African sort grows to a very unusual size, and I saw several which could hardly be less than ten inches long. Scarcely less abundant is the smaller and slimmer species (C. lævigatus), which does not exhibit quite to the same extent the changes of its colour. Rolling its eyes in a very remarkable manner it answered the same purpose as the agama, with its nodding head, of getting up a joke against the Mohammedan fanatics. “What is a chameleon like?” I used to ask them, and not over delighted were they when they were told that the chameleon, with its one eye up and the other eye down, was a faki looking up to God in heaven, but at the same time keeping a sharp look-out upon the dollars of earth.
VALUE OF QUININE.
Thoroughly free, as I have said, from fever, during March and April, I persevered in taking my daily dose of ten grains or more of quinine; but as the heat diminished, and as the rainy season at its height was not so full of miasma, I gradually diminished, and in June and July entirely gave up my uniform administration of the tonic. But quinine still remained my sole medicine, my only resort in every contingency. If ever I got a chill, if ever I was wet through, or was troubled with any symptoms of indigestion, I lost no time in using it, knowing that for any traveller in a region such as this, any indisposition whatever is simply a doorway through which fever insidiously creeps and effects its dangerous lodgment. Any sudden giddiness in the head, or any spasm between the shoulders, or any failure in the functions of the limbs were all, I do not doubt, warnings of the ill-omened visitor, which I accepted in time to avert. Not only, as I have remarked, were fevers here quite common, but my own attendant, who had accompanied me from Alexandria, was prostrated some days by a very serious attack, and his condition of health was so much impaired that he had to be sent back on the next return of the boats. There were others, too, of my own people who had to endure attacks of less severity.
Expecting, as I had been, a much larger fall of rain, I could not be otherwise than much surprised at the meteorological facts which were actually exhibited. Although the rainfall extends over a longer period, the total average fall of water is less here than it is either in Gallabat or in Upper Sennaar, where the rain lasts only from the beginning of May to the beginning of October. There the rain, almost without exception, fell every night, and all night from sunset till daybreak; but here it was the result of experience that the rain ordinarily was to be expected between noon and night. All travelling consequently has to be accomplished before midday, and the journeyings are necessarily shorter than in the dry winter months. It may be taken as a rule that holds good very generally throughout the tropics that if the sun rises clear or becomes clear shortly after rising, there will pretty certainly be no rain for some four or five hours. In Gallabat it was considered rather a feat to walk during the rainy season from one house to another either in slippers or in Turkish shoes, but here, day after day, such protection for the soles of the feet was quite sufficient, even where the ground was not at all rocky.
CLIMATE AND TEMPERATURE.
European vegetables in Gallabat had generally been found to suffer from the excessive wet, and others had either run into weeds or in some way degenerated, but here, from May till August, we cultivated many sorts successfully, and made good use of the intervals which, sometimes for four or six days together, passed without any rain whatever. To confirm what I have said, I adduce the facts that in March 1869, in the centre of Bongoland (lat. 7° 20´ N.), the “Khareef” was opened by four little showers; in April there were seven considerable pourings; in May seven falls of rain, lasting several hours; in June ten, in July eleven, and in August twelve. These must not be reckoned as days of rain, for the truth is, an entire day of uninterrupted rain never once occurred. The rainfall only up to June was attended by tempests or thunderstorms, after which date the violence of them gradually and almost entirely abated. Heuglin in 1863 had made the same observation. At the end of July there ensued an entire change of temperature, and only in exceptionally hot afternoons did the heat ever again reach the extreme point which it had done previously; but even at its maximum it had never exceeded 95° Fahr. in the huts, whilst in the open air it was ordinarily 2° lower. I could now rejoice in a degree of heat scarcely above what is common in our northern zone, and seldom registered a temperature above 77° Fahr. in my own quarters. This fall in the thermometer is very beneficial and refreshing to the European, whose skin, exhausted by repeated perspiration, is very often distressed by a perpetual nettlerash.
The earliest rain which I observed this year fell while I was still at the Meshera on the 2nd of March; and the 16th of that month was the date on which the wind altered its course, and for the first time deviated from its long-prevailing north-easterly direction.
The uniformity of climate in equatorial Africa contributes very much to extend the range of particular species of plants. To this may be added the absence of those mountain systems which elsewhere, as in Asia, traverse the continent in all directions. Without let or hindrance the trade-winds exert their influence over the entire breadth of this region. Any interruption of the rainy season between the two zenith positions of the sun, which in Bongoland are some months apart, has never been authenticated. Although upon the north-west terraces of Abyssinia the rainy season might appear, through the influence of the mountains, to be obliterated or obscure, yet it could always be traced; but nevertheless the whole aggregate of circumstances which contribute to these precedents is not to be estimated during the transitory observations of one short sojourn.
Neither during the continuation of my wanderings towards the south did I find any indication which seemed to evidence that two rainy seasons had anywhere coalesced so as to become one continuous period of rain, which sufficed throughout the year to maintain an uninterrupted renewal of vegetation. Nowhere in the equatorial districts which I visited (not even in the territory of the Monbuttoo, of which the latitude is between 3° and 4° N.) did it appear that there ever failed a uniform period for foliage to develop itself. Apparent exceptions might be found where the condition of the soil is never otherwise than wet throughout the year; but even in this low latitude there is a dry season and a wet season, just as decided as in Nubia, twelve degrees further to the north.