On some disorders indigenous to the country and the causes of them—The distinction of seasons, and the effects thence arising.
THE great respect I entertain for your judgment causes me to take up my pen with diffidence, being aware that my letters are not worthy to meet your eye; but I trust to your kindness to overlook their deficiencies, and to be satisfied with my desire to inform you of all that I have observed in these distant lands.
I remember to have read in certain books of travels that there are men to be met with in the Alps whose necks are covered with swellings, and that the inhabitants look upon them as ornamental.* Similar swellings are often to be seen on persons in this country ; but here the disorder generally attacks the legs, and other parts of the body besides.† The disorder always begins with a fever, which they here call the raging fever, which sometimes causes delirium, and as the strength of the malady increases, great pain is felt in the legs or in other parts attacked : the fever then settling in the suffering part, causes it to swell in a frightful manner. In the commencement of the disorder, the swellings subside again, but as the fever returns, at intervals of one or two months, or a longer period, they reappear and become per-manent ; so that men have been found with legs as thick as my waist and other frightful swellings.
This malady cannot be ascribed to any particular nation or race of men. I remember to have read that it attacks only the St. Thomas’ Christians, and that they may be known by this mark ; but nothing can be more absurd than such a notion, for we see every day people of all kinds, men and women, Mahometans, Heathens, and Christians, and even Europeans who reside here, attacked by it. You, who have given your mind to the investigation of nature, will no doubt be able to give a sufficient reason for these facts: but I trust you will have the goodness to weigh my opinion, which may possibly assist in the explanation.
I believe that the cause of the disorder is in the water and the soil, and partly also in the air, which is filled with vapour drawn up from the water. It appears that in the low lying parts of Malabar in the neighbourhood of Cochin, the earth is full of saltpetre or some other substances, which mingle with the water of the pools or rivers near the sea coast ; and the people who constantly drink this water acquire a disorder and fever which causes at first shivering, and then drives the particles which occasion the fever into a certain part of the system. These particles being sharp and pungent, cause great pain, and at last distend the small vessels in the afflicted region, which after the first access of the complaint, subside again, but after fresh particles have been driven in by fresh fevers, the enlargements not only remain fixed but increase in size. On the legs thus deformed, the flesh becomes loose and spongy ; but this makes them light also, so that however enlarged they may be in size, the patients can walk with great ease.
These remarks of mine seem to be strengthened not only by the taste of the water of these lowlands, which is brackish and unpleasant, but by actual experience ; for the people who are in better circumstances, and can get their water higher up, from the river Mangatti, are seldom visited by this disease, while on the other hand those who drink the water of the neighbourhood suffer from it much. On this account the E. I. Company has wisely ordered that this water should no longer be given out to the garrison, but water from the Mangatti instead ; and it has been observed that the malady has been much less prevalent among the troops since that time. I must add that the juice of the young cocoanuts is also very deleterious ; and my neighbour said that he himself had caught the disorder from that cause. The reason is plain: for we know that the vessels of the cocoanut palm are of great width, so that it imbibes water from the earth just as it is, without detaching it from the particles of saltpetre; and in this state the fluid enters the young nut, the interior of which contains nothing but a sort of water rather sweet in taste, and consequently it gives rise to the same disorder as the water of the wells.
I am so fortunate as never to have suffered from this disease; though I could not escape another, which the natives term Mal-de-terre, which attacked me almost every month, beginning with great uneasiness and pain in the bowels, and ending with violent sickness and diarrhoea. The Indians have a curious remedy for it, which is to take a hot iron and burn the soles of the feet with it. This often has a good effect.
Not to detain you any longer with these painful topics, I shall now turn to descriptions of other natural phenomena, and proceed to relate briefly the courses of the seasons in this part of the world.
One hardly finds here that difference of seasons which is experienced in Europe: for neither are heavy hailstorms,* nor thick falls of snow, nor hard frosts, ever seen or felt in these parts. One must divide the year into two Monsoons,† or seasons, the one being the period of dry weather, the other the period of rain. The dry season may be divided again, first into a temperate season, when the air is tolerably cool: this begins in November, when the atmosphere is bright and clear; the S. E. landwinds then begin to blow, attaining their greatest force in January and subsiding again in February. They blow every morning during this period, and are found by experience to be prejudicial. After this follows the hot season, when, the wind ceasing, the air becomes exceedingly sultry, especially in the forenoon and at night, because there is not the slightest breeze to cool it ; whereas, in the afternoon, there is often a wind from the sea. In the month of May the season begins to change. The heavens become overspread with heavy clouds, and violent storms of thunder and lightning occur. I cannot find that these storms cause so much damage as among us in Holland, the cause of which I take to be the rarefaction of the air through the continued heat of the sun, so that the thunder and lightning finding less obstruction, become more easily diffused and fall to the earth with diminished force. The rainy season sets in at the end of May or beginning of June, and lasts till October, bringing perpetual storms of rain, often accompanied by violent winds. It would be well worth the trouble of any philosopher to enquire into the cause of this rainy season ; and I consider it my duty to speculate upon it, because the phenomena afford some clue to the decision of the question.
In the hot season we find that the wind blows entirely from the North and West : on which account ships then coming from Persia and Surat have a speedy voyage. It is also certain that as, during that time, the powerful action of the sun causes a quantity of vapours to accumulate in those regions, and rain falls there as little as it does here, therefore the N. W. wind must drive those vapours in a south-easterly direction, till they meet the mountain ranges which are a barrier to their further progress. These mountains are the same which stretch from Cape Comorin through Asia. Now the vapours, as they approach these mountains, get more and more condensed : till at length, in the month of May, they are forced down by violent winds, then rebound again, and finally descend in rain on all places situated west of the chain. That these mountains are the true cause of the rainy season appears from the circumstance that when the rainy season sets in on this side of the chain, on the other side, just at the same time, the dry season begins. Hence we are frequently astonished to find that in two places on opposite slopes of the same mountain, one has the rainy and the other the dry weather at the same time : and when, on our side, the rains leave off and the S. E. winds begin to blow, just then the rains commence on the Coromandel Coast.
And while we are on the subject of the weather, I must observe that, in these countries, storms do not last so long as with us in Holland; for, while, there, we often know them continue without intermission for two or three days, here, on the contrary, high winds never maintain their violence beyond an hour or two, when a calm ensues, after which the wind rises again: resembling in this circumstance the sudden whirlwinds (Travades) which navigators encounter in the tropics, and chiefly near the Equator. These storms come on very quickly, and generally end as suddenly. First, a small cloud is seen, which increases rapidly, and then, whirled onwards by a strong wind, bursts in heavy rain. It is very curious to observe how suddenly the clouds gather in the midst of a clear and hot atmosphere. It would seem that some vapours in the lower portion of the atmosphere are prevented by the powerful action of the sun’s rays from collecting together; then, driven up higher than usual, they encounter a cooler stratum of air, by which they are condensed together with all the other vapours that meet them by the way (like the steam condensed on the lid of a tea-kettle); then, urged forward like an ever-increasing snowball, by the force of the wind and the heat of the sun, they become overcharged with weight, and finally precipitate themselves to the earth. A description of this kind of storm or something like it seems to be given us in 1st Kings xviii. 44, 45:—“Behold a little cloud no bigger than a man’s hand rose out of the sea………and it came to pass in the meanwhile that the heavens were black with clouds and wind, and there came a great rain.”
In conclusion, I will note the effects of the rainy season on our roadstead. This it closes up entirely and chokes with sandbanks, on which the repelled waves break with violence. These sandbanks begin to form in the month of May, and are washed away in September and October. Their formation and their destruction are owing partly to the action of the river, and partly to that of the sea; for, at the commencement of the season the river empties itself with great impetuosity into the sea, dragging with it a quantity of sand: on the other hand, the waves of the sea acting in the opposite direction, stop the progress of the sand just where the two bodies of water break upon each other. This is the reason why the sandbanks at that time are constantly augmenting; but, when the force of the sea subsides, and the river has still a vast weight of water to carry down, then the sandbanks are washed away again.