Malabar Manual Vol 1 Chapter 1. The DISTRICT
Section E.—Climate and Natural Phenomena
To understand aright the climate of Malabar it is necessary first of all to glance at a few of the more prominent facts which hold good not only of Malabar, but of all intertropioal countries similarly situated.
And the first and most obvious fact which strikes an observer is the uniformity of temperature throughout the year as tested by the thermometer. The thermometer shows a mean annual temperature on the sea-coast of 81° Fahr. It rarely rises above 900, and it seldom falls below 70°. It may be said in short that it is always hot, sometimes hotter, but never very hot.
This is not solely nor even chiefly due to the great altitude of the sun at midday as very often supposed, for the sun is no higher in the heavens in Malabar at certain seasons than it is in temperate climates. Moreover, the sun shines much longer in summer in temperate climates than it does in Malabar. Further it may be observed that the month in which the sun is at its highest in Malabar, and its hours of shining longest, is by no means the hottest month of the year. At the same time of course it is to be remembered that the altitude of the sun is always great, and its hours of shinning are comparatively long throughout the year, varying as they do from a maximum of about twelve hours and thirty-five minutes in the latter half of June to a minimum of about eleven hours and thirty-five minutes in the latter half of December.
One of the most important factors in maintaining this high temperature is the superheated condition of the surface soil. There is no thick body of cool earth on the surface capable of quickly absorbing the sun’s rays as there is in the temperate zones, where, the range of the thermometer being greater, the depth at which an uniform temperature for the year is reached is deep below the surface of the earth.
The uniform annual temperature depth is soon reached in Malabar, and the consequence is that the surface soil becomes superheated and is constantly radiating its heat both by day and night, and thus maintaining a comparatively high temperature. Another very efficient cause of the high temperature maintained throughout the year is the influence of the aqueous vapour of the atmosphere. It has already been noticed that an ocean current sweeps across from the African and Madagascar shores, and one brunch of it apparently impinges on the coast a little to the north of the district. This brings with it an atmosphere more or less saturated with moisture.
And the ocean itself is always at hand and the sea breeze always highly saturated with moisture blows steadily for several hours of each day in the dry weather. Finally during June, July and August—the south-west monsoon season—the wind blows all day and night long off the ocean and rolls up before it dense masses of vapour. The atmosphere is therefore throughout the year in a more or less saturated condition, and the superfluous heat which, as observed above, is given off by the earth’s surface is, instead of being radiated off into space, very largely absorbed by the aqueous vapour held in suspension in the atmosphere. This aqueous vapour in fact acts like a blanket, preventing the earth from losing heat at night by radiation into space, and the greater the heat is the greater is the capacity of the atmosphere for absorbing moisture.
A cloudless night in Malabar does not, as those who have experienced it can testify, betoken a cool night as it usually does elsewhere.
The above facts are not, however, without their compensating advantages, for the ocean never becomes superheated like the land, and the ocean breezes which blow throughout the year, and in particular the south-west monsoon wind, are comparatively cool winds. In the south-west monsoon season, the temperature of the atmosphere is low in spite of the fact that the sun then attains its greatest elevation in the heavens, and for days, sometimes for weeks together, the dense mass of the monsoon clouds shelters the earth -from the sun’s direct rays.
In fact, so dense and so unbroken is the stratum of clouds in the south-west monsoon season that the uniformity of temperature is chiefly maintained by another cause, namely, by condensation of the atmospheric vapour in the shape of rain. To convert water into steam requires a large amount of heat, and the reverse process, the condensation of aqueous vapour into rain, necessitates the liberation of a large store of heat. So long as the water retains its gaseous form, the heat is insensible, but on being liberated it helps to keep up the high temperature of the air. And this is no doubt what happens to a great extent in the monsoon season when the earth is screened by clouds.
But finally there is also evaporation, a conversion of watery molecules into their gaseous form, in which process a large amount of boat becomes latent or insensible. This goes on in the hours of hottest sunshine. The district is well supplied with rivers and backwaters, and there is besides the ocean always at hand for the sun’s rays to act upon. The heat thus absorbed is great, and evaporation plays no inconsiderable part in moderating the heat and reducing the temperature on land.
Vegetation thrives in such a climate as Malabar possesses, and it is needless to dwell on the luxuriance of grass and shrub and tree presented in Malabar to the eye of a traveller crossing from the arid plains and hot winds of the country east of the ghat mountains. The mountains themselves play an important part in sheltering the country lying to the west of them, for they cool down the winds passing over thorn ; but in the extreme south of the district, where the Palghat gap permits the hot land winds to rush through unimpeded, vegetation receives a severe check in the dry months. Even here, however, the balance of nature is maintained, for heated plains invite the inrush of moist sea breezes, and though the days are hot, the sea breeze lasts longer than it does on the coasts, and brings with it fresh nights and cool mornings even in March and April, the hottest months of the year.
Nor is the climate less favourable to man and animals ; for, as Mr. Wallace in his work on “Tropical Nature” justly observes : “The large absolute amount of moisture always present in the air is almost as congenial to the health of man as it is favourable to the growth and development of vegetation”—(p. 17).
Facts bear out the truth of this remark, and it is matter of common observation that Europeans, who leave the coast in the hot months to seek the coolness and the “sweet half-English Nilgiri air” of the mountains, return after their holiday trip to find their brethren in the plains in the enjoyment of robust health and vigorous constitutions. The best time to seek a change on the coast is in the months when the sky is screened by heavy clouds, when the almost incessant rain of the south-west monsoon has filled the air and the earth with an excess of moisture, and when thick clothing is necessary to stave off maladies arising from the chilly damp.
It is then, too, that animals require extra care and extra comforts in the shape of warm dry beds. It is altogether a mistake to suppose that horses and dogs and cattle generally thrive worse in the humid climate of the west coast than in other places to the east of the mountains. There is absolutely less risk to a heated animal to be exposed to the moist air of the coast climate than to the chilly breezes that prevail at certain seasons elsewhere, and it is matter of experience that with the most ordinary care a sensitively organised animal like the horse enjoys as good health on the coast as inland. All kinds of property, susceptible of damage by excessive moisture, are very liable to be spoilt.
Articles made of leather, the binding of books, furniture whose parts are glued together, instruments made of steel or iron, woollen articles of clothing, silks, etc. require especial care in the monsoon season. They become mildewed, they fall to pieces, they rust, they become spotted, they lose their colours, and, generally speaking, perish unless great care and elaborate drying arrangements are undertaken.
Another most striking point in regard to the climate is the extreme regularity as a rule of the seasons. It once happened to the present writer to be asked one day in the end of the month of February or beginning of March as to the likelihood of rain coming soon, and the reply given on the spur of the moment was that on the 22nd of March at 2 p.m. the first shower would fall. As a matter of fact, the shower did come on that day and at that hour, within ten minutes or so. This was not altogether a haphazard guess, for the 22nd of March is the vernal equinox, and 2 p.m. in the day is precisely the hour at which most frequently the daily battle between sea-breeze and land-wind begins.
In some seasons, though not in all, the first distant rumble of thunder along the line of ghats betokens that 2 p.m. has just struck or is about to strike. This daily battle begins as soon as nature’s pendulum (so to speak) commences slowly to swing back with the passage of the sun across the equator into the northern hemisphere. And so it is throughout the seasons with a regularity as to months and almost to days and hours, perfectly astonishing to people accustomed to live in less settled climes.
The rotation of seasons is very much as follows : towards the end of March or beginning of April the first distant mutterings of thunder are heard among the hills. In some seasons, these thunderstorms occur regularly every afternoon, and occasionally the thundershowers extend as far as the coast line. In other seasons the, advent of these storms is not such a regular daily occurrence, nor is the hour at which they begin so marked. At first the land-wind usually gets the advantage and blows throughout the night; in the forenoon, there is a lull ; then, as the inland surface of the country becomes heated, the sea-breeze rushes in to supply the place of the atmosphere rarefied by the heat. This continues until the thunder-storms commence or until night sets in, for on the coast the sea-breeze declines with the setting sun, and it is only far inland that it continues to blow through the early part of the night. As the season progresses, the western winds from the sea usually gain in force, while the land-winds from the east and north-east fail.
Towards the end of May or beginning of June, the south-west monsoon wind finally obtains the mastery, and the regular rains begin and are usually ushered in by heavy banks of cloud to seaward, by a heavy swell from the west, and by an electric storm of more than usual violence. In some seasons, the electrical disturbance at this time is very great, the roar of the thunder is continuous for many minutes together, and the blaze of the many coloured lightning flashes almost incessant.
In the season of 1873, the duration of one of these thunder-peals was noted. It lasted for no less than thirty-five minutes, during all of which time there was no cessation in the roar of sound, one thunder-peal succeeding another, now near, now far, without a single moment’s interval between them.
The blaze of light, too, at such times is truly awful. Once, however, the south-west monsoon has asserted itself, the thunder-storms cease, the wind settles steadily in the west, and as the season progresses it veers a point or two to the northward of west, although inland it blows steadily all the time from south-west. The explanation of the fact of the wind veering to the north of west is that as it strikes the coast it follows, the direction of the littoral current which at this season runs from north to south. The figures given in the Statistical Appendix No. 1 attest the volume of rain which falls at this season, but even in the heaviest weather one or two hours of each day are free from rain, and there is sometimes a cessation for a fortnight. These long breaks in the monsoon, if there occur with them a fresh breeze and a bright sky with scattered clouds, are most enjoyable, but on the other hand the short intervals between the rain squalls of the monsoon are most oppressive, the air is supersaturated with moisture, the heat is also at the same time great, and of wind there is none.
In the end of September, the south-west monsoon dies away, nature's pendulum (to use the same metaphor) again begins to swing back, and sometimes battles royal again take place between the contending aerial currents, In October, the north-east monsoon or land-wind has usually asserted itself, and with it the rain becomes less frequent, the country begins to dry up, and by the end of December the dry weather has, as a rule, fairly set in.
The period of regular land-winds at night and morning and of sea-breezes during the day then commences and lasts till, with the venial equinox, the period of disturbance again sets in.
Of the south-west monsoon and the discovery by Hippalus —the Columbus of antiquity as he has been called—of its importance to navigators, the following interesting account is taken from M’Crindle’s translation of the “Periplus Maris Erythraei” :
“The whole round of the voyage from Kane and Endaimon Arabia, which we have just described, used to be performed in small vessels which kept close to shore and followed its windings, but Hippalus was the pilot who first, by observing the bearings of the ports and the configuration of the sea, discovered the direct course across the ocean; whence as, at the season when our own Etesians are blowing, a periodical wind from the ocean likewise blows in the Indian sea, this wind, which is the south-west, is, it seems, called in these seas Hippalos (after the name of the pilot who first discovered the passage by means of it). From the time of this discovery to the present day, merchants who sail for India either from Kane or as others do from Aromata, if Limurike be their destination, must often change their track, but if they are bound for Borugaza or Skythia they are not retarded for more than three days, after which, committing themselves to the monsoon which blows rigid in the direction of their course, they stand far out to sea, leaving all the gulfs we have mentioned in the distance.”
It is generally accepted that Hippaios made his discovery in the first century A.D.
Excessive falls of rain are quite common and floods are frequent. On 19th and 20th of May 1882 there was registered a very heavy fall of rain. Several rain-gauges in different parts of the town of Calicut registered from eighteen to twenty-five inches in the twenty-four hours, and as an instance of a heavy fall spread over a longer period in the monsoon of 1871 the rain-gauge at the Collector’s office in Calicut registered over six inches per diem for six consecutive days. But floods do little damage: the rivers have in the course of ages worn down for themselves deep river beds, which, as a rule, contain all ordinary floods, and the common laterite soil of the country is so porous that within half-an-hour of the heaviest shower of rain the roads are dried up, and but for the dripping trees and bushes there would be very little to tell of the rain that had just ceased.
Of unusual storms there are but few records. This is perhaps to be explained by the fact that the mountain peaks of the Western Ghats prevent altogether or disperse any cyclonic tendency of the winds, but the squalls which usher in the south-west monsoon are at times terrific in their violence, and do much damage to ships which have incautiously remained too long on the coast to complete their lading. These squalls are accompanied by mountainous seas, and the wind and waves together generally smash the strongest cables of the best equipped ships. With their anchors gone, the ships usually attempt to set sail, but, the squall being past, the seamen find there is a lull in the wind, while the sea runs as high as ever. If the attempt to make an offing is persisted in, the ship generally drifts slowly into the breaker, and the most skilful seamen usually attempt to beach their ships instead of trying to work them out to sea.
The great storm of the 10th, 17th and 18th April 1847 is perhaps the only occurrence, of the kind of which some details are on record. The storm originated somewhere beyond the southern islands of the Laccadive group. It swept over the islands of Kalpeni and Androth, and did some damage to Kavarathi, but Agatti was apparently beyond the circle of its violence.
Of ninety thousand coconut trees in each of the islands of Kalpeni and Androth the hurricane left only seven hundred standing in Kalpeni and eight thousand in Androth.
Kalpeni was also partially submerged by a wave, and the drinking water of the people in wells was spoilt and their stores of food and their houses destroyed. Of a population of over one thousand six hundred in Kalpeni, four hundred and fifty only remained, but it was estimated that from three hundred to four hundred people only had perished in the storm or of famine afterwards, and that the others had left the island. Of a population of over two thousand five hundred in Androth, nine hundred only remained, the rest having either perished in the storm or dispersed. Two boats with ninety-six males and a number of females belonging to Agatti were caught in the storm and heard of no more. The storm wave dashed on the coast in a very unexpected manner, and its effects were felt from Cannanore to Chetwai.
The wave destroyed the Cannanore Custom house ; it came in so suddenly that the officials had hardly time to escape by the rear as the sea swept in at the front. The wave rushed up the Kotta river and destroyed the Palliyad dam and the cultivation above it over two miles from the mouth of the river. The floods from inland breached the new work on the Conolly canal at Calicut.
At Parappanangadi and Tanur private persons suffered much loss from the sudden rise of the sea. The wave rushed up the Velliyankod river and destroyed the Ayinichira dam and the cultivation above it. The sea also “forced a new and deep opening into the Chavakkad back-water and broke with much strength on the Ennamakkal1 dam, which, however, sustained no injury,” but the crops in the bed of the lake were injured by the floods from inland.
NOTEs: 1. Eight miles from the river month. END OF NOTEs
Earthquakes are fortunately not very frequently experienced, nor, when they do occur, are they destructive in their effects. On the 31st December 1881 at 7:1 a.m. (Madras time) a tremulous motion of the earth, apparently from east to west, was observable at Calicut. It lasted only a few seconds, and the motion which, at Calicut, was unaccompanied by any rumble or noise, was so slight that persons walking and riding out of doors at the time failed to notice anything unusual.
To those indoors, however, the motion was very perceptible, and one or two persons felt sick. This earthquake was preceded by something of the same kind about- mid-night of the preceding night, and a peculiar rumbling and a noise as of rushing waters was heard, but these were so faint that they escaped general observation. This earthquake extended over a wide area, stretching from the Malabar Coast to the Amman Coast and as far north at Khatmandu in Nepal and south as far at least as the Nicobar Islands.
Two months later - on : 28th February 1882 about 6:16 a.m. (Madras time) another smart shock of earthquake was felt at Calicut, but it seems to have been a mere local affair, extending as far north as Tellicherry and as far east as the Nilgiri mountains.
There was the same tremulous motion as on the previous occasion, but the motion gradually increased, and a muffled roar was heard approaching, passing, and dying away. It was like the noise of a short train passing through a tunnel underfoot at the rate of several hundred miles per hour, in a direction from south to north. Furniture and roof tiles and window frames shook audibly for a second. From the first tremulous motion of the earth until everything was again quiet there was no more than an interval of four or five seconds.
At 2 p.m. on 14th October of the same year (1882) the Deputy Tahsildar at Allattur in the Palghat taluk heard a noise as of a train proceeding underground from east to west. He happened to be at the time in office, and the tables and boxes rattled audibly while the shock lasted, which was only for a second or so. Further south earthquakes occur occasionally also, and they have been noticed on the following dates at Trivandrum : —
September 19, 1841.
November 20, 1845.
March 17, 1856.
August 11, 1856—5 h, 56 m. 25 s. A.M.
August 22, 1856—4 h. 25 m. 10 s. P.M. and
September 1, 1856—0 h. 1 5 m. 0 s. P.M.
At various periods of the year, but chiefly towards the close of the rains, the sea and some of the backwaters exhale very offensive effluvia. The water is at times of a dark porter colour, at other times it has been noticed to leave a deposit of black mud on the sand.
Whatever may be the cause of this change in the water, it is invariably fatal to fishes of all sorts, which float dead and dying on the surface and are thrown up by the waves on the beach. The offensive smell is of course largely caused by the putrid fish, but the water itself when thus changed has a peculiar fetid odour.
Many suggestions have been offered to account for the occurrence almost annually of this ked vellam- (bad, stinking water) as the natives call it. Day, in his “Land of the Perumauls,” p. 417, suggests that at Cochin it is due to the emptying of the pits in which coir fibre is soaked before being twisted into rope—the effluvia from which, he very justly remarks, is “most horrible”—and also by the emptying or overflowing of rice-fields in which vegetable matter is allowed to putrefy for manure. These causes do not, however, apply to all the circumstances under which this phenomenon occurs, particularly in Malabar proper, and Dr. Day himself says that “the cause of this effluvia in the sea, during the hot months, is difficult to determine.”
Benell, quoted by Dr. Davy, considered that in Ceylon it arose from the presence of vast numbers of the Arum foptidum. The cause usually assigned, namely, the mixing of the fresh-water from the flooded rivers with the salt-water of the ocean, cannot account for the occurrence of the phenomenon, in November and December, arid an instance of its having been observed at Tellicherry, where also there is no mud bank, in those months of the year 1826 is on record.
It is possible that the phenomenon is connected with that puzzling one presently to be described, which in the very height of the monsoon months vouchsafes calm harbours of refuge for ships on the open coast.
The origin of the mud bays or mud banks which exist at Northern Kollam (near Quilandy), at Calicut, and at Narakal in the Cochin State, and at Alleppey in Travancore, to which some allusion has already been made in the description of the Kadalundi river, has never yet been satisfactorily set at rest. The fact that at Narakal, and sometimes too, at Alleppey mud banks exist, which enable ships to load and discharge cargo in calm water on the open coast all through the south-west-monsoon season is well known.
At Calicut, too, a small mud bank of a similar description is generally present, and at Northern Kollam also. In fact it was at one time supposed (erroneously of course) that the mud bank at Kollam protected the fleet of Vasco da Gama through the monsoon season of 1498, and this and the fact that a ship had lain there in safety the previous year and another had already taken up her position for the season then approaching induced the Joint Commissioners in Malabar in 1798 to permit the Honourable Company's vessel Morning Star to lie under the protection of the mud bank there during the south-west monsoon of that year.
Very heavy weather, however, was experienced, the seas broke-through the bank, and the Morning Star was wrecked, Thu characteristic of the mud banks is that an unctuous mud rises from the bottom of the sea, becomes dispersed in the water, and effectually stills the surf. That the mud is always more or less present at the places named is a fact, but the annual churning up of this mud stratum hardly accounts for all that has been observed, and Mr. H. Crawford, the late Commercial Agent of the Travancore Sirkar at Alleppey, who has perhaps had better opportunities of watching the phenomenon than anyone else, came to the conclusion that subterranean passages or streams communicating with some of the rivers and backwaters “become more active after heavy rains, particularly at the commencement of the monsoon, and carry off the accumulating water and with it vast quantities of soft mud.”
In scanty monsoons the mud banks are less effective as anchorages. He also observed that at seven hundred yards east of the beach at Alleppey pipes were being sunk at a depth of fifty feet to sixty feet when the shafting ran suddenly down to eighty feet and several buckets of mud from this depth were brought up, corresponding in every respect with the mud thrown up by bubbles which he had observed in the sea.
A cone of mud, he said, at time ; appears above the water, the cone or bubble bursts, throwing up immense quantities of soft soapy mud and blue mud of considerable consistence in the form of boulders with fresh water, debris of vegetable matter decayed, and in some instances fresh and green.
Mr. Crawford's successor at Alleppey, Mr. Rohde, confirms the observation, and states that he has seen mud volcanoes bursting up in the sea during the rainy season, to all appearance “as if a barrel of oil had suddenly been started below the surface.” He has come to the conclusion that the mud bank at that place, after being formed in the way above described, is gradually floated away to the southward by the littoral current, and fresh mud banks are formed whenever the hydraulic pressure of the inland backwater increases sufficiently to overcome the subterranean resistance offered by the stratum of fluid mud which exists at the spot described by Mr. Crawford.
A further proof, he observes, of the truth of this is to be found in the fact that the extent of mud bank at Alleppey increases and diminishes as the level of the inland waters rises and falls, and this was most observable in the monsoon season of 1882.
Of the mud itself, Dr. Day gives the following account: “The mud feels unctuous and sticky, but is not gritty unless mixed with the sand. It is of a very dark greenish colour, and has but a slight odour. Under the microscope it shows ‘very minute angular fragments of quartz, the largest hardly visible without a lens : this is the sand. Secondly, — Foraminferous shells, of the genus rotalia, and a few fragments of larger shells. Thirdly, — Diatomacea, of which were discovered species from upwards of twenty genera. Fourthly,—a few spicules of sponges and corals, very minute: and some amorphous matter which was not destroyed after long boiling in strong acids.’
On a more elaborate enquiry1 the mud was found to be very tenacious and resistant of pressure, like a stiff piece of jelly; and it is supposed that, acting like an immense spring, it yields to the pressure of the waves, that the water thus loses its force and becomes quiescent2 whilst the mud expanding is prepared for a fresh encounter. An examination into its composition resulted in the discovery of sixty-two species belonging to thirty genera, of the class Cryptogamia and sub-group Diatomae." — Land of the Perumauls, pp. 36, 37.
NOTEs: 1. Madras Journal of Literature and Science. New Series, No. XII. p. 264
2. While these pages have been passing through the press, Mr. King, of the Geological Survey, has written a paper on the subject, in which, for the first time, it is conclusively proved that “a sensible amount of oil” exists in the mud. And the oil, as Mr.. King points out, may be in part at least the sufficient cause of the quiescence of the sea. The oil, Mr. King thinks, is ‘derived perhaps in part from the decomposition of organism (in the mud), but principally from the distillation of oil in subjacent lignitoferous deposits belonging presumably to Warkilli Strata'. He also suggests that this distillation of oil from the lignitiforous Warkilli deposits may be due to 'moderate heat arising from a line of volcanic energy," “possibly lying parallel to the west coast of India". — Record, Geol, Surv., Vol. XVII, Pt. I, 1884, p. 14. END OF NOTEs
These phenomena, owing perhaps more to natural difficulties than to any lack of interest in the subject, have not yet been exhaustively investigated, but the following statement of facts is perhaps justified by the observations so far made. The occurrence of the Iced vellum (stinking water) and the existence of the mud banks are not necessarily connected : fish can live in the latter, but not in the former.
The former probably owes its deadly character to the generation from subjacent strata by volcanic heat of poisonous matter or vapour which is absorbed by the water; and the latter, while possibly deriving some of their mud oil from similar volcanic causes, are also replenished, in one instance at least, by subterranean passages, full of liquid mud, communicating with the sea on one side and the backwaters on the other.