_February_ is dry and hot during the day, but the nights are cloudless and cool, and the moonlight singularly agreeable. Rain is rare, and when it occurs it falls in dashes, succeeded by damp and sultry calms. The wind is unsteady and shifts from north-east to north-west, sometimes failing entirely between noon and twilight. The quant.i.ty of rain is less than in January, and the difference of temperature between day and night is frequently as great as 15 or 20.[1]
[Footnote 1: Dr. MACVICAR, in a paper in the _Ceylon Miscellany_, July, 1843, recorded the results of some experiments, made near Colombo, as to the daily variation of temperature and Its effects on cultivation, from which it appeared that a register thermometer, exposed on a tuft of gra.s.s in the cinnamon garden in a clear night and under the open sky, on the 2nd of January, 1841, showed in the morning that it had been so low as 52, and when laid on the ground in the place in the sunshine on the following day, it rose to upwards of 140 Fahr.]
[Sidenote: Wind N.E. to N.W.
Temperature, 24 hours: Mean greatest 87.7 Mean least 73.1 Rain (inches) 2.1]
_March_.--In March the heat continues to increase, the earth receiving more warmth than it radiates or parts with by evaporation. The day becomes oppressive, the nights unrefreshing, the gra.s.s is withered and brown, the earth hard and cleft, the lakes shrunk to shallows, and the rivers evaporated to dryness. Europeans now escape from the low country, and betake themselves to the shade of the forests adjoining the coffee-plantations in the hills; or to the still higher sanatarium of Neuera-ellia, nearly the loftiest plateau in the mountains of the Kandyan range. The winds, when any are perceptible, are faint and unsteady with a still increasing westerly tendency, partial showers sometimes fall, and thunder begins to mutter towards sunset. At the close of the month, the mean temperature will be found to have advanced about a degree, but the sensible temperature and the force of the sun"s rays are felt in a still more perceptible proportion.
[Sidenote: Wind N.W. to S.W.
Temperature, 24 hours: Mean greatest 88.7 Mean least 73.6 Rain (inches) 7.4]
_April_ is by far the most oppressive portion of the year for those who remain at the sea-level of the island. The temperature continues to rise as the sun in his northern progress pa.s.ses vertically over the island. A mirage fills the hollows with mimic water; the heat in close apartments becomes extreme, and every living creature flies to the shade from the suffocating glare of mid-day. At length the sea exhibits symptoms of an approaching change, a ground swell sets in from the west, and the breeze towards sunset brings clouds and grateful showers. At the end of the month the mean temperature attains its greatest height during the year, being about 83 in the day, and 10 lower at night.
[Sidenote: Wind N.W. to S.W.
Temperature, 24 hours: Mean greatest 87.2 Mean least 72.9 Rain (inches) 13.3]
_May_ is signalised by the great event of the change of the monsoon, and all the grand phenomena which accompany its approach.
It is difficult for any one who has not resided in the tropics to comprehend the feeling of enjoyment which accompanies these periodical commotions of the atmosphere; in Europe they would be fraught with annoyance, but in Ceylon they are welcomed with a relish proportionate to the monotony they dispel.
Long before the wished-for period arrives, the verdure produced by the previous rains becomes almost obliterated by the burning droughts of March and April. The deciduous trees shed their foliage, the plants cease to put forth fresh leaves, and all vegetable life languishes under the unwholesome heat. The gra.s.s withers on the baked and cloven earth, and red dust settles on the branches and thirsty brushwood. The insects, deprived of their accustomed food, disappear underground or hide beneath the decaying bark; the water-beetles bury themselves in the hardened mud of the pools, and the _helices_ retire into the crevices of the stones or the hollows amongst the roots of the trees, closing the apertures of their sh.e.l.ls with the hybernating epiphragm. b.u.t.terflies are no longer seen hovering over the flowers, the birds appear fewer and less joyous, and the wild animals and crocodiles, driven by the drought from their accustomed retreats, wander through the jungle, and even venture to approach the village wells in search of water. Man equally languishes under the general exhaustion, ordinary exertion becomes distasteful, and the native Singhalese, although inured to the climate, move with la.s.situde and reluctance.
Meanwhile the air becomes loaded to saturation with aqueous vapour drawn up by the augmented force of evaporation acting vigorously over land and sea: the sky, instead of its brilliant blue, a.s.sumes the sullen tint of lead, and not a breath disturbs the motionless rest of the clouds that hang on the lower range of hills. At length, generally about the middle of the month, but frequently earlier, the sultry suspense is broken by the arrival of the wished-for change. The sun has by this time nearly attained his greatest northern declination, and created a torrid heat throughout the lands of southern Asia and the peninsula of India. The air, lightened by its high temperature and such watery vapour as it may contain, rises into loftier regions and is replaced by indraughts from the neighbouring sea, and thus a tendency is gradually given to the formation of a current bringing up from the south the warm humid air of the equator. The wind, therefore, which reaches Ceylon comes laden with moisture, taken up in its pa.s.sage across the great Indian Ocean. As the monsoon draws near, the days become more overcast and hot, banks of clouds rise over the ocean to the west, and in the peculiar twilight the eye is attracted by the unusual whiteness of the sea-birds that sweep along the strand to seize the objects flung on sh.o.r.e by the rising surf.
At last the sudden lightnings flash among the hills and sheet through the clouds that overhang the sea[1], and with a crash of thunder the monsoon bursts over the thirsty land, not in showers or partial torrents, but in a wide deluge, that in the course of a few hours overtops the river banks and spreads in inundations over every level plain.
[Footnote 1: The lightnings of Ceylon are so remarkable, that in the middle ages they were as well known to the Arabian seamen, who coasted the island on their way to China, as in later times the storms that infested the Cape of Good Hope were familiar to early navigators of Portugal. In the _Mohit_ of SIDI ALI CHELEBI, translated by Von Hammer, it is stated that to seamen, sailing from Diu to Malacca, "the sign of Ceylon being near is continual lightning, be it accompanied by rain or without rain; so that "the lightning of Ceylon" is proverbial for a liar!"--_Journ. Asiat. Soc. Beng._ v. 465.]
All the phenomena of this explosion are stupendous: thunder, as we are accustomed to be awed by it in Europe, affords but the faintest idea of its overpowering grandeur in Ceylon, and its sublimity is infinitely increased as it is faintly heard from the sh.o.r.e, resounding through night and darkness over the gloomy sea. The lightning, when it touches the earth where it is covered with the descending torrent, flashes into it and disappears instantaneously; but, when it strikes a drier surface, in seeking better conductors, it often opens a hollow like that formed by the explosion of a sh.e.l.l, and frequently leaves behind it traces of vitrification.[1] In Ceylon, however, occurrences of this kind are rare, and accidents are seldom recorded from lightning, probably owing to the profusion of trees, and especially of coco-nut palms, which, when drenched with rain, intercept the discharge, and conduct the electric matter to the earth. The rain at these periods excites the astonishment of a European: it descends in almost continuous streams, so close and so dense that the level ground, unable to absorb it sufficiently fast, is covered with one uniform sheet of water, and down the sides of acclivities it rushes in a volume that wears channels in the surface.[2]
For hours together, the noise of the torrent, as it beats upon the trees and bursts upon the roofs, flowing thence in rivulets along the ground, occasions an uproar that drowns the ordinary voice, and renders sleep impossible.
[Footnote 1: See DARWIN"S _Naturalist"s Voyage_, ch. iii. for an account of those vitrified siliceous tubes which are formed by lightning entering loose sand. During a thunderstorm which pa.s.sed over Galle, on the 16th May, 1854, the fortifications were shaken by lightning, and an extraordinary cavity was opened behind the retaining wall of the rampart, where a hole, a yard in diameter, was carried into the ground to the depth of twenty feet, and two chambers, each six feet in length, branched out on either side at its extremity.]
[Footnote 2: One morning on awaking at Pusilawa, in the hills between Kandy and Neuera-ellia, I was taken to see the effect of a few hours"
rain, during the night, on a macadamised road which I had pa.s.sed the evening before. There was no symptom of a storm at sunset, and the morning was bright and cloudless; but between midnight and dawn such an inundation had swept the highway that in many places the metal had been washed over the face of the acclivity; and in one spot where a sudden bend forced the torrent to impinge against the bank, it had scooped out an excavation extending to the centre of the high road, thirteen feet in diameter, and deep enough to hold a carriage and horses.]
This violence, however, seldom lasts more than an hour or two, and gradually abates after intermittent paroxysms, and a serenely clear sky supervenes. For some days, heavy showers continue to fall at intervals in the forenoon; and the evenings which follow are embellished by sunsets of the most gorgeous splendour, lighting the fragments of clouds that survive the recent storm.
[Sidenote: Wind S.W.
Temperature, 24 hours: Mean greatest 85.8 Mean least 74.4 Rain (inches) 6.8]
_June_.--The extreme heat of the previous month becomes modified in June: the winds continue steadily to blow from the south-west, and frequent showers, accompanied by lightning and thunder, serve still further to diffuse coolness throughout the atmosphere and verdure over the earth.
So instantaneous is the response of Nature to the influence of returning moisture, that, in a single day, and almost between sunset and dawn, the green hue of reviving vegetation begins to tint the saturated ground. In ponds, from which but a week before the wind blew clouds of sandy dust, the peasantry are now to be seen catching the re-animated fish; and tank-sh.e.l.ls and water-beetles revive and wander over the submerged sedges. The electricity of the air stimulates the vegetation of the trees; and scarce a week will elapse till the plants are covered with the larvae of b.u.t.terflies, the forest murmuring with the hum of insects, and the air harmonious with the voice of birds.
The extent to which the temperature is reduced, after the first burst of the monsoon, is not to be appreciated by the indications of the thermometer alone, but is rendered still more sensible by the altered density of the air, the drier state of which is favourable to evaporation, whilst the increase of its movement bringing it more rapidly in contact with the human body, heat is more readily carried off, and the coolness of the surface proportionally increased. It occasionally happens during the month of June that the westerly wind acquires considerable strength, sometimes amounting to a moderate gale.
The fishermen, at this period, seldom put to sea: their canoes are drawn far up in lines upon the sh.o.r.e, and vessels riding in the roads of Colombo are often driven from their anchorage and stranded on the beach.
[Sidenote: Wind S.W.
Temperature, 24 hours: Mean greatest 84.8 Mean least 74.9 Rain (inches) 3.4]
_July_ resembles, to a great extent, the month which precedes it, except that, in all particulars the season is more moderate, showers are less frequent, there is less wind, and less absolute heat.
[Sidenote: Wind S.W.
Temperature, 24 hours: Mean greatest 84.9 Mean least 74.7 Rain (inches) 2.8]
_August_.--In August the weather is charming, notwithstanding withstanding a slight increase of heat, owing to diminished evaporation; and the sun being now on its return to the equator, its power is felt in greater force on full exposure to its influence.
[Sidenote: Wind S.W.
Temperature, 24 hours: Mean greatest 84.9 Mean least 74.8 Rain (inches) 5.2]
_September_.--The same atmospheric condition continues throughout September, but towards its close the sea-breeze becomes unsteady and clouds begin to collect, symptomatic of the approaching change to the north-east monsoon. The nights are always clear and delightfully cool.
Rain is sometimes abundant.
[Sidenote: Wind S.W. and N.E.
Temperature, 24 hours: Mean greatest 85.1 Mean least 73.3 Rain (inches) 11.2]
_October_ is more unsettled, the wind veering towards the north, with pretty frequent rain; and as the sun is now far to the southward, the heat continues to decline.
[Sidenote: Wind N.E.
Temperature, 24 hours: Mean greatest 86.3 Mean least 71.5 Rain (inches) 10.7]
_November_ sees the close of the south-west monsoon and the arrival of the north-eastern. In the early part of the month the wind visits nearly every point of the compa.s.s, but shows a marked predilection for the north, generally veering from N.E. at night and early morning, to N.W.
at noon; calms are frequent and precede gentle showers, and clouds form round the lower range of hills. By degrees as the sun advances in its southern declination, and warms the lower half of the great African continent, the current of heated air ascending from the equatorial belt leaves a comparative vacuum, towards which the less rarefied atmospheric fluid is drawn down from the regions north, of the tropic, bringing with it the cold and dry winds from the Himalayan Alps, and the lofty ranges of a.s.sam. The great change is heralded as before by oppressive calms, lurid skies, vivid lightning, bursts of thunder, and tumultuous rain.
But at this change of the monsoon the atmospheric disturbance is less striking than in May; the previous temperature is lower, the moisture of the air is more reduced, and the change is less agreeably perceptible from the southern breeze to the dry and parching wind from the north.
[Sidenote: Wind N.E.
Temperature 24 hours: Mean greatest 85 Mean least 70 Rain (inches) 4.3]
_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-sh.o.r.e-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.
[Footnote 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 quant.i.ty one-third greater than the total rain in England throughout an entire year.
[Footnote 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 a.n.a.logy 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 sh.o.r.e 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 alt.i.tude, the rains are carried further towards the interior, and whilst the weather is unsettled and stormy on the eastern sh.o.r.e, the western is comparatively exempt, and enjoys a calm and cloudless sky.[1]
[Footnote 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 quant.i.ty 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 princ.i.p.ally 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]
[Footnote 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 dest.i.tute 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.]