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tropical regions. It is thus that while the weather in summer is fine, the wind generally becomes stronger with us as the day advances, and lulls away towards the evening, which gives, to that time of day, the eneffable sweetnefs we have all so often experienced.
This may be called a faint embrio of the sea breezes of tropical regions. On the more northerly coasts of Greece, the Levant, and the African fhores of the Mediterranean, the sea breeze is distinctly perceived, during the summer season.
Such are the effects arising from the diurnal changes in our northern climates; the effects of the annual revolution are still more sensible. To this cause we are to attribute the prevalence of the west winds, during summer, even in our climate, and the much more marked prevalence of them, during that season in Spain, and France. For the continent of land to the eastward, being much more heated by the long continued action of the sun's rays upon it, during summer, than the waters of the Atlantic ocean, the wind is perceptibly drawn towards the east during that season.
But the effects of the seasons, in altering the winds in those countries which approach towards the tropics, are much more powerful than with us. For when the sun approaches the tropic of Cancer, and acts perpendicularly, or nearly so, during the whole course of a lengthened day on the countries of Persia, Bengal, China, and the adjoining states, the surface of the land there, at that period, becomes so much more heated than the sea to the southward of it, that the current of the general trade wind is interrupted so as to flow, at that season, from the south to the north, which is
sons of the year, the low countries of eastward of it, become, in summer, so
than Africa, at that season, that the air drawn from thence to the eastward. TH the trade wind, in the Indian ocean, fro October, (that is, during the summer mo in a north-east direction, which is precisel of that of the general trade wind, in open same latitude. But when the sun leaves hemisphere, and retreats towards the tropi corn, these northern countries are allow and the general trade wind is then suffered its natural direction.
Such are the obvious causes of that peri ing wind in the Indian seas, which has be nated the monsoon. To account for the s tions in its direction, which are observed ferent tracts of those seas, will be an easy any one who has made himself master of th of the phenomena here explained. At would lead to too great length to take notice
By inspecting the map, the attentive r observe, that no monsoon takes place to the of the line, excepting in that part of the oce ing to the large and newly explored ifland, ca Holland; an ifland fo much exceeding, in other island on the globe, as to deserve, in sense, the name of a continent. In that globe, the same causes concur to produce a
as in the northern hemisphere, and similar phenomena are also experienced. From the month of October till April, (that is, during summer in the southern hemisphere) the monsoon sets in from the N. W. to S. E. directly opposite to the course of the general trade. wind, as happens also in the northern ocean, during their summer; and here also, as in the northern hemisphere, the general trade wind resumes its usual course, during the winter season,
Nothing can more perfectly fhow the justness of the theory of monsoons here given than this single fact does; and though the writer of this essay thinks it of much more consequence to make useful discoveries than to be at much trouble about ascertaining to whom these discoveries of right belong, yet he hopes it will not be deemed impertinent in him, after a silence of 18 years, now, for the first time, barely to hint that the above explanation of the monsoons was first publifhed by him, in the Encyclopedia Britannica, in the month of July 1773, while Mr Cooke was yet out on his first voyage of discovery, and from which he did not return till seven months after this essay was published, at which time the writer of this essay, from the state of the winds that had been observed, without hesitation foretold what has since been found to be truth by succeeding navigators, that there did not exist, nor ever would be found any continent, or large islands in the southern hemisphere, near the tropics, unless it was New Holland alone. He takes notice of this circumstance here, chiefly because it affords the strongest proof that can be required of the justnefs of the explanation given, and also because it thus reVOL. vii.
In a future number, some periodica take place in particular parts of the torrid are of less extensive influence than the m gether with the smaller deflections of t themselves, will be taken notice of. At reader fhall be no longer detained tha point out to him one of those beautiful an arrangements in nature, which the atten has so often occasion to remark, and to ad
In the great South Sea, and Atlantic O the general trade winds invariably prevail sail, very easily, between the tropics, f west, by the help of the unchanging e that there prevails; but when he attemp the eastward, in the same seas, he finds sible the wind blows continually agains has no other resource, therefore, than to to the southward, or the northward till high latitudes, where the trade winds do
There he meets with variable breezes, of which he is enabled to prosecute his voy fect. But if land fhould have run along, tion nearly parallel to the equator, within of the trade winds, so as to have prevented getting into the latitude of the variable w would have happened if the general trade there invariably prevailed? All navigatio must have been interrupted, as the winds been continually opposite to the course of
Instead of this destructive arrangement, we have seen that the very lands in India which prevent a fhip from reaching to the latitude of variable breezes, naturally, and necessarily produce, first a diurnal sea and land breeze to help them out, or into a harbour with ease, almost in any situation; and next, the monsoons, which by blowing six months in one way, and six months in the opposite direction, afford a sure and easy mode of navigating in those seas, in all directions, if the proper seasons be only adverted to.
How wonderful, O Lord! are all thy works; in wisdom and in mercy hast thou made them all!
OBSERVATIONS ON WATSON'S HISTORY,
For the Editor of the Bee.
Of those who have laboured in the field of modern history, the first place is perhaps due to Robertson, an historian who unites, in the highest degree, the profound views, and accurate knowledge of the philosopher, with the bold and beautiful imagination of the poet. He is one of the most singular examples of genius being made entirely subservient to truth. Genius has always certain topics upon which it loves to dwell, certain views which it loves to take, and favou rite characters which it delights to describe; but the unvaried aim of this writer is philosophical truth, and his favourite topic, universal virtue. Though pofsefsed of a mind naturally fitted to contemplate only what