At the equator all the stars rise and set and the periods of both are equal. Night and day are constant in twelve hours each, and the move­ment of the celestial sphere is circular. In the first of Aries and Libra the sun is in the zenith and casts two shadows, and at these two periods where the temperature is equable over the greater part of the <Greek>, at the equator the heat is excessive and the gnomon has no shadow. When the sun passes the first of Aries and inclines to the north, the shadow is thrown to the south, and when he passes the first of Libra and moves southwards, the shadow is cast to the north. The year has six seasons. Two summers, from the 1st° of Aries to the 15th° of Taurus, and from the 1st° of Libra to the 15th° of Scorpio; two winters, from the 1st° of Cancer to the 15th° of Leo, and from the 1st° of Capricorn, to the 15th° of Aquarius. At the change of the Sun into Cancer, the temperature rises in the climatic zones inclined from the equator, whereas at the equator it is the beginning of winter. It has also two springs, from the 16th° of Leo to the end of Virgo, and from the 16th° of Aquarius to the end of Pisces; and two autumns, from the 16th° of Taurus to the end of the Gemini and from the 16th of Scorpio to the end of Sagittarius. Avicenna and some learned men maintain that the equator is the most equable in temperature of all coun­tries, because the seasons of cold and heat follow in close succession and the sun does not remain long in the zenith. Fakhr-Rázi* and another school select the fourth climate and say that “although the sun's stay in the zenith is but for a short period, on the other hand he is never more remote than 23 degrees and a fraction, and we observe that in places where the greatest altitude of the sun is less than its altitude at the equator, as for instance at Khwarizm, where his altitude on the first of Cancer is 71° which is 5° lower than his altitude at the equator, the people are much inconvenienced by the heat, while at the equator it is the cold season. But as the altitude there is 5° greater, it follows that the winter of the equator should be hotter than the summer of Khwarizm; what then would its summer be? And the colour and appearance of the Ethiopians who are near the zone of the equator support this view.” The partisans of each school, maintain their several opinions at considerable length. The true resolution is this, that equability in the sense of approximate similarity of conditions is more apparent at the equator, and great heat on account of this assimilation, is to a certain extent unfelt, because the sensations caused by physical impressions succeeding each other rapidly have less force, while sensations directly antagonistic are more perceptible though disre­garded in view of the equality in the constant proportions of heat and cold. In the first mentioned sense, therefore, Avicenna is correct, while in the latter, the opinion of Ar Rázi is tenable. Every place which has not the equinoctial and its pole directly in the zenith is accounted among climatic zones inclined from the equator, and these are specially differentiated in five classes. The first is in a latitude less than the greatest declination of the Sun from the equator: the latitude of the second is equal to the greatest declination: that of the third is greater than the declination but less than its complement measured from the equator: that of the fourth is equal to the complement: that of the fifth is greater than the complement but less than 90°. In the first, the sun is twice in the zenith, from the 1st of Aries to Cancer and from the 1st of Cancer to Libra and casts here also two shadows. In the second he is only once in the zenith, in Cancer. Here and in the remaining zones where the sun does not culminate, the shadow is thrown to the north. At the spot where the pole of the equinoctial is directly perpendicular it is 90° and the movement of the celestial sphere is like a mill. The year there forms a nycthemeron as has already been explained. There is no doubt that the fabled darkness* which is the tradi­tion of the vulgar, refers to the gloom of these nights. The points of the east, west, north and south are not here distinguishable.

Some divide the <Greek> into three parts. The first is from the equator to a position the latitude of which is equal to the greatest declina­tion of the sun from the equator. The inhabitants of this region are called Sudán (blacks), because the sun shining directly above them, they are coloured by its rays and their hair is curly. Those who dwell proximate to the equa­tor are called Zingis.* They are absolutely black and scarce resemble human beings. Those who live near the region of the greatest declination, are less swarthy and being of moderate stature and equable disposition, are more of a class with the natives of Hindustan, and Yemen and some of the Mauri­tanian Arabs. The second is the region of which the latitude extends from the greatest declination to a quarter parallel with the Great Bear.* The colour of its inhabitants is inclined to fairness and as the sun does not shine perpendicularly above them and yet is never far removed, their bodies are fashioned in a naturally-adjusted mean, as the Chinese, the Turks, and the people of Khurásán, Iráḳ, Persia and Syria. Of this race, those who dwell nearest to the south have a subtler intellect because they are nearer the zodiac and the orbits of the five planets, while those are of a more powerful build who inhabit the regions to the west. Proximity to the east produces a softness of frame and by such as these great deeds are never accomplished. The third region is parallel with the orbit of the Great Bear such as the country of the Sclavonians and Russians, and as it is distant from the Zodiac and little affected by the heat of the sun, the cold impels to hardihood, moisture is predominant, and natural living products do not mature. Their colour is fair, their hair red and worn long, their bodies sleek, their temper fierce and their disposition inclined to evil. Hermes,* the most celebrated of the name, divides the earth into seven parts analogous with the seven spheres, one within the other. The first towards the south is the continent of India: the second, Arabia, Yemen, and Abyssinia: the third, Egypt, Syria and Mauritania: the fourth, Persia: the fifth, the Greeks, Sclavonians, Franks: the sixth, the Turks and the Khazars: the seventh, China, Khotan and Tibbet.

It is said that Noah apportioned the length of the habitable globe into three lots. The southern he gave to Ham, and this is the country of the blacks and the Arabs: the northern to Japhet, where the fair-skinned, ruddy faced races dwell: the middle portion was assigned to Shem, inhabited by the wheat-coloured people. Feridún divided the breadth of his dominions into three parts; the eastern he gave to Túr: the western to Salm and the intermediate tract to I´raj. Some of the Greeks have made two sections of the habitable earth latitudinally from Egypt. The eastern they call Asia, the western which is the Mediterranean Sea, they subdivide into two, that on the south being named Libya, the country of the negroes, and that on the north Europe* where dwell the white and ruddy-complexioned races. Bisecting Asia from the angle between the east and north transversely in a southerly direction, they divide it into two segments, of which the inner is the less and the outer the greater. The middle is called Asia Minor and comprises the country of Irán, Ḥijáz, Yemen and Khurásán. The outer is Asia Major, comprising China,* India and Sind. Some say that Hindu philosophers partition the habitable earth into a diagram of nine parts, viz., the south (dahkhin) the Arabian country; the north (uttar), that of the Turks; the east, (púrab), China; the west, (pachchim), Egypt and Barbary; the north-east (ísán), Khata and Khotan; the north-west (báyab), the Greeks and Franks; the south-west (nairit) the country of the Copts and Berbers, Africa and Spain. The middle country was called Madhya-desa.* But this account is not found in this order in any Sanskrit work nor is it thus handed down by any of the learned of this country.