But inland there are considerable tracts of elevated country which present climates by no means to be despised, and which will no doubt in time, with the advance of civilisation, become eligible and healthy sites for European occupation, and more than one example of climatic conditions that appear decidedly inviting will be found amongst the tables furnished below.

An example of the climate of the Sahara has already been furnished in the notice of Algeria, and in the northern part of the continent the only other at all well-known climate (apart from Egypt) is the Soudan.

Practically rainless in parts, the climate is intensely hot and dry, the relative humidity showing one of the lowest records in our collection; but as the equatorial zone is approached a moderate rainfall develops, and throughout the region the large daily range of temperature results in the nights being comparatively cool, and therefore less trying than many parts of India. The northern portion is too dry to be very unhealthy, apart from the danger of abdominal chills, but as we ascend the Nile it expands into the immense marshes described by Baker and others, which are necessarily intensely malarious, while round the great lakes the sleeping sickness, previously rare or unknown there, is spreading rapidly.

Commencing with the dry Soudanese region, climatic tables of three stations will be found below, the first and most northern of which, it will be seen, is practically rainless. The figures of the first table are averages of ten years’ observations.

The two remaining tables are for the year 1901, and are not even complete in places. Kassala is, of course, much nearer the sea than Omdurman, and hence its better rainfall.

Abyssinia.

—The greater part of the Ethiopian empire is high ground, and in many parts of the country the climate may almost be described as temperate, as may be judged from the following statement (derived from a French official source) of the climatic factors of the capital during the year 1901.

The Region of the Great Lakes.

—Turning now to the great lakes of Central Africa, the following data from Hann’s “Klimatologie” may give some notion of the conditions prevailing.

In the Victoria Nyanza region (at E.F., 3,900; E.M., 1,200), according to E. G. Rauenstein, the mean annual temperature is 71·2° F. (21·8° C.), March 73·7° F. (23·2° C.), July 67·7° F. (19·8° C.), October 75·2° F. (24·0° C.), December 71·7° F. (22·0° C.). The extreme mean monthly maxima and minima (of January and February), 94° to 54° F. (34·4° to 12·2° C.), and the absolute maximum and minimum, 99·7° and 50·2° F. (37·7° and 10·1° C.).

The average rainfall for nine years was as follows:—

In the north (Uganda) the climate is warm and moist, though without excessive rainfall, but the air is a good deal drier along the southern coast.

In Tanganyika, in lat. 4° S., long. 29° E. (E.F., 2,670, E.M., 813), the mean annual temperature is 76·7° F. (24·8° C.), the mean of the hottest month (of October) being 81·7° F. (27·6° C.), and of the coolest, in December, 74·2° F. (23·4° C.), the extremes being 90·7° and 64·4° F. (32·6° and 18° C.). The rains occur in April and May and November and December, while from June to September is dry, the annual rainfall being 50 ins. (1,270 mm.).

Further south, Zoruba, in Nyassaland, has a total rainfall of 62·23 ins. (1,581 mm.), falling on 144 days in the year, but should otherwise be a pleasant climate, as the relative humidity is usually low.

The capital, Blantyre, at E.F., 3,280, E.M., 1,000, is naturally even cooler, but has a heavier rainfall, distributed as below:—

The Congo Basin.

—The climate of the basin of the Congo is notoriously unhealthy, especially as the portion as yet opened up seldom extends far beyond the low malarious banks of the great river and its tributaries. The warmest month is February or March, and the coldest July or August.

Hann gives the following table of the temperatures of the following stations:—

These are typical equatorial climates, the greatest range between the means of the coldest and hottest months being at most 9·5° F. (5·3° C.), while in one case the range is less than one degree of the Fahrenheit scale, and though the temperatures are in no case excessive, the dampness of the atmosphere makes the heat of a very trying character, especially in certain localities, as at Stanley’s Pool, where during August and September there are certain peculiar night-winds which, not unfrequently, are the cause of cases of heat apoplexy, and this although the highest temperature recorded is but 97°, at Brazzaville.

There are two rainy seasons, in April and November. The dry period falls in June and July, but is not very marked in the interior.

The table on next page will give an idea of the amount and distribution of the rainfall.

On the West Coast

, at Bathurst, the highest temperature occurs in October, during the period of the greater rains, the annual extremes being 98·8° F. (37·1° C.) and 57·4° F. (14·1° C.); the greatest daily variation of temperature being met with during the dry season, January to April, when it amounts to about 20° F. (11·5° C.). The rainfall varied during eleven years from about 32 ins. (813 mm.) to 78 ins. (1,980 mm.). In December, a cool morning breeze known as the Harmattan sets in, and continues till February or March. The rains begin in June and end in September.

At Sierra Leone

, in spite of its lying north of the equator, the distribution of the monthly temperature resembles that of the Southern Hemisphere, the minimum falling in August, while the hot season lasts from February to May. The mean annual temperature is 77·6° F. (25·4° C.), and the average annual extreme temperatures 97·5° F. (36·4° C.) and 64·8° F. (18·2° C.). No month is absolutely rainless, and the annual rainfall is very heavy, ranging from 100 ins. (2,540 mm.) to 204·5 ins. (5,230 mm.).

Curiously enough, the Cape Verd Islands are very dry, although they agree generally as to temperature with the coast, tempered by their insular position and the influence of the trade wind, having a rainfall of only about 10 ins. (260 mm.), the most rainy month being September.

Gulf of Guinea.

—Along this coast there is a double rainy season; the greater from March to the end of July, and the lesser in October and November; with the dry season in August and September, and the cool Harmattan blowing between November and March. In speaking of the Harmattan as a cool breeze, it must be remembered that one refers only to the sensations produced by it; for as a matter of fact, it has no appreciable effect on the mean temperature, and feels cool only by virtue of the accelerated evaporation from the skin caused by its intense dryness. On the coast it really raises the mid-day temperatures, although it renders the mornings and evenings cooler. In the interior the Harmattan may figure indeed as a hot wind, and may be additionally disagreeable on account of the red dust it carries.

The rainfall is everywhere very heavy, that of the Cameroon district reaching the enormous figure of 350 ins. (8,970 mm.), the second greatest in the world.

The mean annual temperature is about 77° F. (25° C.), with annual extremes of 89·6° F. (32° C.) and 68° F. (20° C).

The following table of the climatic data for the coast of British Nigeria will give a fair idea of the conditions that will be met with in the coast towns of the group of colonies in this region:—

The remarkable uniformity of the temperature data is very striking. In the interior of Nigeria, however, much higher temperatures are experienced, especially at the times when the hot Harmattan is blowing off the northern deserts, the noon temperature at such times being rarely under 100° F. (37·8° C).

As we get farther south the temperature moderates and the rainfall rapidly diminishes; the mean temperature in Angola being no more than 68° F. (20° C.), while in the elevated interior the climate is neither disagreeable nor unhealthy.

Dr. Yale Massey sends me the following information from his Mission station in the Benguela district, at 4,700 feet, lat. circa 12° S.; and long. 17° E. “The distinctly wet months are from October to April inclusive, and this is also the hot season. There are usually a few showers in September, and rarely some in May, and during the dry season there is usually a strong breeze. In the wet season the mid-day temperature ranges from 80° to 100° F., at night from 45° to 60° F.; while during the dry weather the mid-day temperature is from 70° to 90° F., and at night even slight frost may occur. As might be expected from the elevation and climate, this is a generally healthy locality, but there is a certain amount of fever, most of the cases occurring in April and May.”

East Coast.

—The reputation borne by the east coast is scarcely more enviable than that of the western, the accounts of travellers voyaging on the Zambesi being generally alternate wails on attacks of mosquitoes and upsets from hippopotami. The rainfall is, however, much lighter, and at corresponding latitudes the temperatures generally seem somewhat lower.

Owing to the presence of a considerable Arab element, the population have attained, in some places, a larger grade of civilisation than is the case on the west coast, so that the introduction of hygienic measures might be somewhat more practicable, albeit that Arab civilisation, per se, has hardly reached the stage of promoting sanitation.

The two following tables of a tropical and subtropical station, each on this coast, will give some general conception of the conditions prevailing.

Madagascar.

—With the exception of the littoral, which is rather warm and extremely malarious, the greater part of this island is too elevated to present a really hot climate, but the rainfall in the interior is rather heavier than on the mainland, that of the capital, Antananarivo, being 52·4 ins. (1,331 mm.), which is distributed as follows:—

The Island of Mauritius.

—Latitude circa 20° 20′ S. The mean annual temperature of Port Louis is 77·2° F. (25·1° C.), the absolute extremes of temperature in nineteen years being 89° and 53·5° F. (31·6° and 11·9° C.), and the mean relative humidity 74 per cent., so that in the matter of heat there is nothing to be feared; but unfortunately malaria, which was quite unknown in the earlier days of its colonisation, is now very rife and of a very obstinate type. The rainfall amounts to 74·5 ins. (1,892 mm.), which is rather heavier than that of Madagascar, and is distributed as below:—

The southernmost portions of Africa, Cape Colony, &c., do not belong to the category of hot climates, either in climate or in their diseases, and so need not be considered here.

Red Sea and its Coasts, including Somaliland.

—The horrors of the climate of the Red Sea are too well known to need comment. The whole region is almost rainless, subject to suffocating calms, and the presence of the large, but completely land-locked, sheet of water renders the relative humidity constantly high. Moreover, the whole basin is comparatively shallow, so that it becomes highly warmed even in its depths. At its southern end the temperature of the water at the surface may reach 95° F. (35° C.), and 90° F. (32·2° C.) has been registered at a depth of 5 fathoms. In the Gulf of Suez, pleasantly fresh days may be met with during winter, but in the south the mean temperature of a day seldom falls below 80° F. (26·7° C.), and in July the mean maximum temperature exceeds 108° F. (42° C.) July is the hottest month, but there is little to choose between the discomforts of any of the four months, June to September. The least hot month is January, but the climate is a singularly uniform one, the night bringing comparatively little relief, and when followed by a breeze of about the same speed as the ship, cases have occurred in which steamers have actually been obliged to put about and steam against the wind, in order to prevent the crew from falling victims to heat apoplexy.

North of lat. 19°, the prevailing winds are from the north or north-west, while in the south the predominating winds are from the south and south-east, between the two lying a belt of variable winds. From June to August north-west winds prevail over the whole Red Sea. This is known as the “Kamsin,” or fifty days’ wind, the word being derived from the Arabic root of that numeral, which, originally, intensely hot and dry, rapidly takes up moisture from the water, and is hence particularly insupportable on the Arabian side of the sea; though the fine sand with which it is loaded makes it equally objectionable from another point of view on the African side. Its velocity is often considerable, and under such circumstances may be even dangerous to the lives of those who are so unfortunate as to be exposed to its fury in the open desert. The extremely fine dust penetrates everywhere in spite of closed doors and windows, reaching even ships far out at sea. Fortunately, on the coast it is generally a good deal modified by sea-breezes springing up in the afternoon, but there is also a tendency to fall dead calm at night, under which circumstances the dark hours are even more intolerable than those of the day.

The following table of the principal climatic data of Massawa in the Italian colony of Erythrea, compiled from data contained in a pamphlet by Dr. Giovani Petella, of the Royal Italian Navy, gives a good idea of the character of the climate of the Red Sea littoral.