ページの画像
PDF

observe, if it were not in contradiction to publick opinion, that the cold produced is not a peculiar property of the wind, but depends upon the general principle, that all liquids passing into an aériform state, absorb heat, and cause immediately around them a diminution of it, and consequently a relative coldness. On the same principle depends also the cooling of wine and water, in the land-wind seasons, the latter in light earthen vessels, which allow an oozing of the water through their pores, and the former in bottles, wrapped in a piece of cloth, or in straw, which must be constantly kept moistened. . The great violence of these winds is at last terminated by frequent showers of rain, in June, in the low countries, and by the greater quantity of the regular rains falling in the inland countries, which seem to suspend the partial formation of clouds along the Ghauts, and to leave them clearer, and visible at a greater distance, than they had been at any other period of the year before. After the enumeration of so many disagreeable circumstances, I am naturally led to an investigation of the causes that produce them. Before this can be done, however, I must prove, according to promise, that the theory of our philosophers is founded in errour. They ascribe, as already observed, the extraordinary heat which distinguishes these winds from most others, to the absorption of calorick, in their passage over an extensive tract of country, at a time when the sun acts most powerfully in our latitudes. According to this theory, the heat should increase in proportion to the space over which this wind is to travel, it should be hotter on the coast, than it is at any part of the

country inland, or, which is the same, it should decrease by degrees from the eastern to the western sea of the peninsula. Experience, however, teaches us the reverse; for it is hottest near the Ghauts, and among the valleys between those ranges of hills, than at any place on the coast; and the heat of those winds decreases also as they approach the Bay of Bengal, and in a direct ratio from the Ghauts to the sea: accordingly, it is at Ambore hotter than at Vellore, and at this place again than at Arcot, Conjeveram, and Madras, where the landwinds are seldom felt with any degree of severity. Time is another measure applicable to the acquisition of heat, as it increases to the greatest pitch which a body is capable of receiv. ing in proportion to its continuance: the land-winds should therefore be cooler when they set in at ten or eleven o’clock, and hottest at their termination in the afternoon; they should be so at least at noon, when the sun is nearly vertical, and has the greatest influenee on the substances from which heat is to be attracted. The contrary, however, comes nearest to the truth; for it is known that these winds set in with their greatest violence and heat at once, which rather abate than increase, as might be expected. We should, on this principle, further suppose the heat would increase gradually with the return of the sun to our latitudes, from its southern declination, and stand always in proportion to its position. We find, however, that experience also contradicts this point of the theory under discussion; for after the sun has passed our zenith,” the land-winds set in at once with all their intensity, in the manner before described, and they cease as abruptly before its return again.t

* The sun is in the zenith at Madras about the 26th of April. # The sun is again in our zenith on its southern declination about the 19th August.

A material change in the temperature of this climate is certainly effected by the approach of the sun from the south; but the heat which is thus caused, and which increases by imperceptible degrees, is never so great, and is only felt by those who expose themselves to it unprotected; for the air remains proportionally cool, and our houses afford, in this season, a pleasant retreat. We find it far otherwise in a land-wind; for this penetrates our inmost recesses, and renders life miserable every where. I have before observed, that winds equally hot with those of periodical duration, are felt in all parts of the country, and at different seasons; a circumstance alone sufficient, if proved, to overthrow the groundwork of the old theory. For a confirmation of this, I will appeal to the general observation, that immediately before a long rain the weather is sultry, and that a single shower is always preceded by a warm, disagreeable wind. We are very particularly reminded of the approaching great monsoon in October, by the oppressive heat we have in the calm evenings of that month, which, I am persuaded, would equal that of the landwinds in May, if the atmosphere were not cooled in the latter part of the night by breezes that have wafted over extensive inundated plains. I can refer, secondly, to my meteorological journal, according to which, the 4th of June, 1800, at Madavaram, a place not far from Bengalore, the thermometer rose for a short time to 104° just before a slight shower of rain, and at a time when heavy clouds darkened the western hemisphere. Further, in the months of March and April, 1804, we had often at Bengalore, in the afternoons, strong gusts of wind from the eastward, which, in common, were styled landVoI., v. 3 G

winds, and were really as hot and disagreeable as moderate land-winds are in the Carnatick. I could have multiplied instances of this kind, but am of opinion that in a fact so much known, it would be perfectly needless. The last refuge of the defenders of this theory, is the valleys of the Ghauts, in which they pretend the heat is generated by the concentrated and reflected rays of the sun. I will not deny but the heat occasioned by these causes, may contribute much to raise the heat of the land-winds; but the sudden appearance of the latter, their usual strength, and abrupt disappearance, all militate against that explanation as a principal cause. The heat of these winds should in this case, to say a few words more on the preceding subject, decrease regularly, from the point where it is greatest towards the opposite, on both sides, as is the case on the coast of Coromandel. On the contrary, we find that, immediately on our having ascended the Ghauts, or on the top of hills elevated above the clouds, we have escaped their heat all at once. It is hereby remarkable, that the direction of the wind, remains to appearance nearly the same every where. In Mysore, for example, the wind is, in the land-wind season, west during the greater part of the day; in the afternoon it is from the east, and commonly warmer than the former. This, together with what had been said before, will, I hope, be thought sufficient to establish my opinion relative to what cannot be the cause of the heat in the land-winds. It remains now to point out a theory supported on a firmer basis, which 1 shall endeavour to do in the following pages. It is founded on a chymical principle, and will explain, I think, the heat of these winds in, a satisfactory manner.

The principle itself needs no demonstration, as it is admitted as a general law; viz. that “all bodies, when they become more dense, suffer heat to escape; or, what is the same, they give out heat.” For example, when gases or aeriform substances become vapours, they discharge as much heat as was necessary to keep them in their former gaseous state: further, vapours in condensing into fluids, are known to do the same, as also fluids acquiring solidity. I am sorry that the quantity of heat set free in the condensation of vapours required for a pound of water, has escaped my memory; but I recollect it was very considerable. We know, however, that a great deal of it is required for the evaporation of the same measure, and it is but reasonable to admit that the same quantity with which it has combined should be discharged on its returning to its former state of fluidity. In order to apply this principle to explain the presence of heat in our land-winds, I must first observe, that the atmosphere in January, February, and March, is perfectly clear and serene; and then I will call to mind what has been said of the phenomena of those winds, that they are preceded by clouds on and among the Ghauts, and that a heavy shower of rain from that quarter announces their arrival; that during their continuance, clouds are observed to lie on the Ghauts; and that the atmosphere, even in the low country, is hazy and thick. I must add also, that the countries west of the Ghauts are at this season frequently visited by heavy showers of rain, accompanied with much thunder and lightning, and sometimes with hail. Here, in the Mysore country, I have found the heaviest showers of this kind to come from the northwest, which is exactly in the direction of the countries remark

able for the great heat of the landwinds in this season. At times, we have also showers from the east and southeast, and my attention shall not be wanting to ascertain whether it is not at the time when the landwinds blow hottest in the Carnatick. By this we see, that the clouds formed on the Ghauts, charged with water and electricity (by causes I am not now to investigate) are drawn to the westward, whilst the heat, which, during the formation of these clouds, must necessarily be discharged, is carried to the east, or to the lower parts of the coast, and causes the properties for which the land-winds are so remarkable. I have acknowledged already, that the heat occasioned by the power of the sun in this season, contributes to the aggregate of it in the wind; but I must observe also, that it acts only as a secondary cause, and passively, by preventing its absorption and diminution in the career over a variety of substances, particularly moisture, with which it would combine, if they had not been previously removed or incapacitated. In colder climates, this absorption takes place in a greater degree, as substances are abundant with which the heat produced by the formation of rain can combine and become imperceptible. It is, however, there also often remarked, that the heat of the sun in a cloudy day is more powerful than at any other time. In common this is ascribed to the reflection of the rays of the sun from the clouds; but I opine it is often the consequence of the formation of water in the clouds, which obscure the sky at that moment. It has been observed, that the heat of the land-winds is not felt on the top of high hills, or on plains of a very inconsiderable perpendicular height above those in which it rages most violently; as, for example, in Mysore near the Ghauts, which is only about five hundred

feet higher than the valleys immediately below. This might be considered a weighty objection against my theory; as heat, considered in the light of an elastick fluid, expands equally on all sides; and, from whatever cause it proceeds, it should be supposed to extend even further where it meets with less resistance, as from the air in higher regions, which is known to be lighter and more penetrable than near the earth. But the reverse takes place; for almost immediately above the clouds no other heat is perceptible than what might be owing to the nature of the climate.

This circumstance may be accounted for by the diminished density of the air in the lower parts of the country, produced by the heat of the season, which would natural

ly cause the wind to rush thither, with all its contents, and with greater impetuosity. The coolness of the atmosphere on elevated situations may be ascribed also to the evaporation of the uppermost strata of the clouds, which accompany the land-winds. Many arguments I have dispensed with, which might have been produced to elucidate and to establish my theory, as they were chiefly such as could be collected from simple inference, and from affirmative application of doctrines advanced before. - I will only add, that both the sirocco and samiel may be owing to similar causes as those which appear to be productive of the pernicious, or rather disagreeable, effects of our land-winds.

CURSORY INFORMATION ON THE SUBJECT OF CERVANTES AND DON QUIXOTE.

SO little is really known of the biography of Cervantes, that those Spaniards who design to do him honour by learning the particulars of the life of a man whose writings have had so great an effect on their own country, and have so greatly amused all parts of the world, know not by what means to procure complete memoirs of him. Of the incidents authenticated, the following is a part. The accuracy with which his work has been investigated, the venial failures of memory detected in it, and the account obtained of the property of its author, are so many proofs of Spanish zeal and industry, in behalf of the literature of their country. They will, therefore, be found interesting by British readers,

w

as well from that cause as from the curiosity of their contents. In the first page of the History of Don Quixote, it is said that on Saturday the Don's dinner consisted of duelos y quebrantos. Shelton [the first English translator] calls it collofts and eggs: all the other translators say, griefs and groans; grifies and grumblings; Pellicer has thus explained the meaning in a note. “It was customary in some parts of la Mancha for the shepherds to convey to their masters’ houses, the carcases of the sheep or cattle which had died during the week. After taking out the bones, the flesh was salted and preserved for culinary use: and broth was made of the broken bones. In allusion to the painful recollection of the loss of part of their flocks, the sorrow it occasioned, and the breaking of the bones, such food was called duelos y quebrantos; sorrows and breakings.”

The books which have been printed in Spain during these last forty years, both in verse and prose, have constantly the mark of interrogation reversed before a question, and also at the end, in the usual way. M. de Florian has suited his translation to the present French taste. He says he is convinced that Cervantes composed the first part of Don Quixote, at a single cast [d'un seul jet] or as the Italians say, by the first intention, without even giving himself the trouble of revising his manuscript, as is evident from the number of anachronisms.

The duration of the history of Don Quixote, is thus computed by Senor Rios in the three splendid editions made of that history, under the direction of the Royal Academy at Madrid, published in four large quarto volumes, 1780, in 4 vols. 8vo. H782, and in 6 smaller 8vo. volumes in 1787, with 36 copper-plates and a map of Spain on which is traced the route of the Don, specifying where every one of the adventures is supposed to have happened.

The first edition of Don Quixote was in 1605, and as we are to imagine Cervantes described the manners of his own times, we shall, from the text, state the following computation.

[blocks in formation]
[blocks in formation]

But although Cervantes intended that the third and last sally should be interwoven with the two first, and without any further interval than the above stated months, it, notwithstanding, appears from the context of the history that no less than ten years intervened: supposing the hero contemporary with several events in the year 1614. Such as the expulsion of the Moors; the adventures of Roque Guinart; the date of Sancho's letter to his wife from the duke's castle, July 20, 1614; the satyrical remarks on the second part published in the same month and year by Avellaneda, and the age of the housekeeper which in the first chapter is stated to be above forty, and in the last chapter but one more than fifty.

The principal purpose of the history of Don Quixote, was, as Cervantes himself tells us in his prologue to the first part, “ to invalidate the authority and favour in which the world, and especially the vulgar, held books of chivalry,” which delicate method of ridicule, happily became effectual, according to that wise sentence of Horace:

[blocks in formation]
« 前へ次へ »