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distribution of the clouds, and the appearance of other Meteors; the relation of which to the state of the Thermometer, Barometer, and Hygrometer, have not been duly noted; that is to say, there has been no discoverable peculiarity in the state of those instruments at the time: but the actions of De Luc's Aërial Electroscope have been intermitted, or otherwise irregular and inconstant.
As the peculiarities of weather alluded to are characterised by difference in the distribution of the clouds in general, and of other Meteors, and do not consist in the varieties of any one cloud in particular; and as the former part of this work has related chiefly to the varieties of individual modification, it is purposed to consider briefly, in this place, the characteristic circumstances of different kinds of weather. In doing this, I have taken examples of some of the most dissimilar varieties, though there are kinds of weather partaking more or less of each of them, so that the shades of difference are innumerable, every day, perhaps, having something different from all the rest in the year and if the different states of weather alluded to have any decided connexion with the varieties of the animal functions, their
effects must be very intricate and compound; a circumstance which has always rendered the knowledge of this connexion so obscure and imperfect.
As there are many circumstances which constitute particular kinds of weather, and many combinations of these circumstances, it will be proper to adopt some one as a criterion, and speak of the combinations of the others under that head.
The order of the clouds is the most obvious feature in different kinds of weather, and ought to be principally attended to. There are several sorts of weather, which, to an inattentive observer, would be called, in common, fine wholesome weather; but which, by a more minute observance, are found to differ materially, both in their appearance and consequences.
A stratus early in the morning, greater or less, according to the time of year, &c. evaporating as the Sun rises, the formation of well defined hemispherical Stackenclouds through the day, most abundant soon after noon, and disappearing again in the evening, to be succeeded by strong Dew and a Fallcloud, are the circumstances which mark a settled and wholesome state of the
Atmosphere, particularly when accompanied by Westerly Breezes; which though they do not vary directly as the Sun's altitude, yet seem, in some measure, to keep pace with it, and a calm succeeds in the evening.
This order and distribution of the clouds happens with different Winds, and different states of the Thermometer; for it is not confined to hybernal frost, nor to the heat of the Dog Star. When it takes place, however, the mercury in the Barometer is seidom very low or variable. Indeed it may be said, in general, to be conjoined with a mean state of that instrument. This weather is of longer or shorter continuance, as may happen: the appearance of cirrus and cirrostratus, and above all, the fleecy and irregular look of the cumuli, with sudden variations in temperature and pressure, indicate a change. Sometimes these appearances soon subside, and the same weather returns. The cumuli, too, occasionally become rocklike, approach to cumulostratus, and spread, without ending in Rain; but these are exceptions to the general rule. When to such a continuance of regular nimbification, as described above, cirrocumulus supervenes, an increased warmth often follows, and frequently without Rain.
Occasional changes of this kind in the order of the clouds, unattended by Rain, took place during the long drought, which continued from Midsummer nearly to Michaelmas, in the year
In days with the regular order of clouds alluded to, I have found the action of De Luc's Electric Column regular. Such days
often alternate with others in which different modifications appear; and very often after, cumulostratus, accompanied by cirrus, &c. has prevailed for many days: nimbification and Rain take place; after which, only regular cumuli are observed again; as if nimbification was a process which restored the tranquillity of the Atmospheric Electricity.
In spring and autumn we have frequently a continuance of cloudless days, ushered in by more or less of a stratus; but this very clear kind of weather seldom takes place about the solstices. The Wind is usually Easterly, varying more or less to North or South, and often strong: the air dry; the mercury of the barometer usually above the mean altitude; and the range of the thermometer, that is, the distance between the maximum of the day, and the minimum of the night, is considerable, The
falling of the Dew in the evening, which is often plenteous, is indicated by the crimson or lake colour of the horizon for some time after sunset, which extends all around, except perhaps, in the West, where the Sky has a deep and rich golden appearance, approximating more to red, to yellow, or to orange*. Nearly a week of
It is very difficult to commemorate precisely the particular tints exhibited by clouds; yet this ought to be done as accurately as possible: for the different colours, refracted by the haze, with a horizontal Sun, are very various, on different occasions, though the Sun's distance from the horizon, either above or below, shall be the same. The haze, at different times, refracts almost every conceivable variety of purple, lake, crimson, orange, and yellow, and sometimes a brownish colour. The colour of the haze should be distinguished from that refracted by definite clouds. The latter also refract a great variety of colours, and sometimes many tints are seen in different parts of the same cloud. Though the infinite shade of colours will ever prevent the adoption of terms which shall define them precisely; yet a much better nomenclature for colours might be invented, than has hitherto been done. It is obvious how indefinite the present terms in common use are. How different the red of the Pœony from that of the Papaver Rhaeas, and still more so from that of the Papaver Orientale, or the Scarlet Lichnis. The yellow of the Crocus, or the Marigold, from that of the Evening Primrose, or the Ranunculus pratensis. Perhaps the best mode of forming a nomenclature for colours, would be by reference to specific flowers, which may be considered as standards.