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MR. WHISTLECRAFT'S WEATHER ALMANACK.

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with many nice observations and kind reflections. As an author he is well known and esteemed.

We have, therefore, a long roll of years of antiquity, down to the present time, all testifying to the influence of the moon upon the weather. Is all this opinion wrong? The public, or popular authority, has not proved or demonstrated the fact, but boldly assert it. While the scientific world--the eminent and learned—have not disproved it, although they have not approved of it, except in some few instances. The question is still in abeyance. Whatever may be the merits or demerits of the lunar influence, it positively bespeaks recurring monthly periods. There seems to be some alliance between the lunar influence and the monthly recurring periods. If the lunar theory is correct, the monthly recurring periods must be so; but the recurring monthly periods do not of necessity establish the lunar influence. I will just dot down, from Mr. Whistlecraft's “ Weather Almanack,” the days of change of weather of 1857.

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January
February
March
April
May
June
July
August
September
October
November
December

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6546 :5 :77

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24 23

24
23

170

RECURRING MONTHLY PERIODS.

Here is evidently a long array of recurring monthly periods or dates, assigned to and dependent upon and deduced from the changes of the moon. It must be borne in mind that the critical days of the recurring monthly periods are not the days of change of weather, commonly so called; but the recurring monthly periods are the highest and lowest states of the instruments; they are, in fact, analogous, in some degree, to the time of high and low water. They are, in some degree only, days of change; but they are more properly the fixed, settled conditions of the weather, whichever way that may be. Thus, the 11th of February, 1845, would be the result of the continuance of some days' previous cold, and not the day of change to that extent. Because the days of highest or lowest barometer are not attained generally at once by a sudden transition.

In respect, however, to the value of the lunar weather table, its extreme accuracy as to the effect of two hours' difference in the time of her changing, should produce such difference in the weather, seems very remarkable ; and this precision as to the small amount of time producing such great effects, is scarcely to be received. And in respect to change of weather, it may seem rather odd to ask what is really meant by change of weather, for that is at present a very undefined state.

. Are we to consider a change of wind, or temperature, or from wet to dry, etc., because some of these are changing very much almost every day ? Until we have some well defined condition, we are in the dark, and each may be always right or wrong.

CHAPTER VII.

Important effects of the Wind.—Action of the Wind on Barometer and Thermo

meter.—North and South Winds. -Sea and land Breezes of the Tropics.Causes of the sea and land Breezes.—Gravity or weight, the force or pressure producing motion.- Horary motion of the Barometer.-All-controlling power of the sun.—Lunar influence inappreciable.—Diurnal heating and cooling of the Air.—Diurnal oscillations of the Barometer. - Motion of the air produced by heat.-High pressure at the verge of the Tropics.- Barometer at Macao and Havannah - Barometer at Madras and Bombay.—The trade winds. Inclination of the trade winds to the Ecliptic.— The power of the sun in the Tropics.—Cool winds in the Tropics.— The temperate and changeable Climates. — Prevalence of the warmer winds.-S. W. winds characteristic of our climate.—Gulfstream of minor influence.-S.W. winds transformed into N.W. winds.- Prevalence in upper regions of a N.W. current.-China may be the origin of our N. E. winds.-China and England reciprocate.—In the winds two conditions co-existent.-Passage of the S.W. gales northward.—Greenwich and Orkney Barometer.-Orkney a suitable station.—The Barometric Pressure regular and progressive.-S.W. gales, supposed course and termination. Results of the Anemometer at Greenwich. - Proportion of the Winds - Preponderance of the S.W.-Deficiency of the S.E.

CHAPTER VII.

THE WIND.

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Having attempted to ascertain the lunar atmospheric influence by stating the evidence as given by diverse authorities, and as well as we could the coincidences of the changes of the moon with the recurring monthly periods, thereby inferring that, if the moon did act in the manner stated by those who entertained a favourable opinion of her influence, then it followed, as a necessary consequence, that there must be recurring monthly periods. The lunar periods are well known, and the accordance of the recurring monthly periods of the barometer and thermometer lend the aid of a demonstrable and conspicuous fact to the supposition that the moon may have some secondary, subsidiary, or regulating agency.

But we must carry our investigation a little further before we unhesitatingly assign this controlling power to the moon.

There is nothing more obvious to common

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