December.—In December the sun attains to its greatest southern declination, and the wind setting steadily from the northeast brings with it light but frequent rains from Bay Of Bengal. The thermometer shows a maximum temperature of 85° with a minimum of 70°; the morning and the afternoon are again enjoyable in the open air, but at night every lattice that faces the north is cautiously closed against the treacherous "along-shore-wind."
Notwithstanding the violence and volume in which the rains have been here described as descending during the paroxysms of the monsoons, the total rain-fall in Ceylon is considerably less than on the continent of Throughout Hindustan the annual mean is 117.5 and on some parts on the Malabar coast, upwards of 300 inches have fallen in a single year[1]; whereas the in Ceylon rarely exceeds 80, and the highest registered in an exceptional season was 120 inches.
1: At Mahabaleshwar, in the Western Ghauts, the annual mean is 254 inches, and at Uttray Mullay; in Malabar, 263; whilst at Bengal it is 209 inches at Sylhet; and 610.3 at Cherraponga.
The distribution is of course unequal, both as to time and localities, and in those districts where the fall is most considerable, the number of rainless days is the greatest.[1] An idea may be formed of the deluge that descends in Colombo during the change of the monsoon, from the fact that out of 72.4 inches, the annual average there, no less than 20.7 inches fall in April and May, and 21.9 in October and November, a quantity one-third greater than the total rain in England throughout an entire year.
1: The average number of days on which rain fell at Colombo in the years 1832, 1833, 1834, and 1835, was as follows:—
| Days. | |
|---|---|
| In January | 3 |
| February | 4 |
| March | 6 |
| April | 11 |
| May | 13 |
| June | 13 |
| July | 8 |
| August | 10 |
| September | 14 |
| October | 17 |
| November | 11 |
| December | 8 |
| Total | 118 |
In one important particular the phenomenon, of the Dekkan affords an analogy for that which presents itself in Ceylon. During the south-west monsoon the clouds are driven against the lofty chain of mountains that overhang the western shore of the peninsula, and their condensed vapour descends there in copious showers. The winds, thus early robbed of their moisture, carry but little rain to the plains of the interior, and whilst Malabar is saturated by daily showers, the sky of Coromandel is clear and serene. In the north-east monsoon a condition the very opposite exists; the wind that then prevails is much drier, and the hills which it encounters being of lower altitude, the rains are carried further towards the interior, and whilst the weather is unsettled and stormy on the eastern shore, the western is comparatively exempt, and enjoys a calm and cloudless sky.[1]
1: The mean of rain is, on the western side of the Dekkan, 80 inches, and on the eastern, 52.8.
In like manner the west coast of Ceylon presents a contrast with the east, both in the volume of rain in each of the respective monsoons, and in the influence which the same monsoon exerts simultaneously on the one side of the island and on the other. The greatest quantity of rain falls on the south-western portion, in the month of May, when the wind from the Indian Ocean is intercepted, and its moisture condensed by the lofty mountain ranges, surrounding Adam's Peak. The region principally affected by it stretches from Point-de-Galle, as far north as Putlam, and eastward till it includes the greater portion of the ancient Kandyan kingdom. But the rains do not reach the opposite side of the island; whilst the west coast is deluged, the east is sometimes exhausted with dryness; and it not unfrequently happens that different aspects of the same mountain present at the same moment the opposite extremes of drought and moisture.[1]
1: ADMIRAL FITZROY has described, in his Narrative of the Voyages of the Adventure and Beagle, the striking degree in which this simultaneous dissimilarity of climate is exhibited on opposite sides of the Galapagos Islands; one aspect exposed to the south being covered with verdure and freshened with moisture, whilst all others are barren and parched.—Vol. ii. p. 502-3. The same state of things exists in the east and west sides of the Peruvian Andes, and in the mountains of Patagonia. And no more remarkable example of it exists than in the island of Socotra, east of the Straits of Bab el Mandeb, the west coast of which, during the north-east monsoon, is destitute of rain and verdure, whilst the eastern side is enriched by streams and covered by luxuriant pasturage.—Journ. Asiat. Soc. Beng. vol. iv. p. 141.