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the 24th, and continued until about three in the afternoon. At four in the morning the wind veered to the north. The quicksilver fell to the eighth degree, in the hall of the house; and if exposed to the open weather, would have sunk nine or ten degrees lower.

...At Sag Harbour, Henry P. Dering, Esq. remarked that the evening of the 23d was moderate, and almost a calm, until near midnight. The sky, however, was overcast, and somewhat lowering. The wind then shifted suddenly from the southward to about north, and blew with uncommon violence. It shortly after began to snow, and the tempest swelled to a hurricane. The vessels at the wharf received considerable damage. Several of them parted their fasts and drove ashore.

At Litchfield, in Connecticut, in about latitude forty-two degrees north, the sun rose clear on the morning of the 23d, and the weather was mild. But it grew cold until near noon, when the wind came round to the southeast. The weather then moderated, and was misty, though the wind was yet chilly. The snow on the ground became soft, and appearances indicated rain. But about four o'clock in the afternoon it began to snow, and this continued without any wind until ten o'clock, P. M. Afterwards, about two o'clock in the morning of Tuesday the 24th, the storm had become violent, both as respected snow and wind; and a furious gale blew from the north, or nearly north, until some time in the night of the 24th. Many sheep, in this county, froze to death. One man lost ten cows out of sixteen, and some of them were congealed in the erect posture, standing upon their legs.

It appears from these facts, that the commotion in the atmosphere on this occasion, had become very serious off Cape Hatteras as early as 8 o'clock, P. M., of the 23d. It had commenced at New-York by midnight. The snow had began to fall at Plandome by one o'clock on the morning of the 24th; by two, at New-London, and by four, at Boston.

This amounts to eight hours of difference in the time of its commencement off Cape Hatteras, and of its beginning at Boston; and computing the distance between these two places to be six hundred miles, the storm must have advanced to windward at the rate of seventy-five miles an hour.

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No. IV.

HINTS relative to the most Eligible Method of conducting METEOROLOGICAL OBSERVATIONS. By JOHN GRISCOM, Member of the Medical Faculty of Queen's College, New-Brunswick, (New-Jersey,) Professor of Chemistry in Columbia College, &c.

[Read before the Society December 8th, 1814.]

An accurate register of a careful and extensive series of observations on atmospherical phenomena, under the direction of this society, might, it is conceived, very usefully contribute to enlarge our knowledge of the nature of those changes, so important to human welfare, and to throw into the common stock of philosophy, facts conducive to its advancement.

Vicissitudes of weather are regarded, by the greater part of mankind, as events altogether fortuitous in their nature, and subject to influences, the precise order of which cannot be ascertained.

Philosophers cannot, indeed, boast of much progress in this field of discovery. Governed, as those changes doubtless are, by chemical, rather than by mechanical laws, it is not to be expected that mankind will ever arrive at that perfection of knowledge, with respect to these phenomena, which has crowned their labours in relation to the heavenly bodies. But, although an acquaintance with the ultimate principles upon which atmospheric changes depend, may never be attained, it is scarcely to be doubted, that a diligent course of observation and experiment, performed by men of science, in various parts of the globe,

would furnish results which might serve as a foundation for a theory much more perfect than any which has been proposed.

Facts of such common occurrence, and so fully within the reach of observation, as are those of wind, rain, storms, changes of temperature, &c. are, doubtless, susceptible of arrangement and classification, as well as those in other departments of natural science. It is well known that people whose peculiar situations and employments habitually stimulate them to these observations, acquire an unusual degree of skill in the prognosis of weather.

It is thus that shepherds and sea-faring men become deeply versed in the varying physiognomy of the sky. But the knowledge thus incidentally acquired, and insulated from public convenience, were it reduced to something like method and system, might be attained and communicated with the same facility and rapidity as other portions of physical science.

The invention and use of instruments, especially of the thermometer and barometer, have enabled the moderns to arrive at much greater precision than the ancients in their acquaintance with the nature of the atmosphere, and of its agency in the operations of the globe. But the application of those instruments has hitherto been too much limited to a few whom curiosity has occasionally prompted to employ them. In the operation of causes which are coextensive with whole climates, and wide-spread regions of the earth, it is not to be expected that a few detached observations can be sufficient to establish general laws.

We live in a period, however, in which the spirit of philosophy seems more than ever awake to the interests of humanity; and deriving, as we do, so many important advantages from the sagacity and industry of our progenitors, it becomes our reasonable duty to extend the same benefits, as far as we are able, in a progressive ratio to our

successors.

Grounded upon views of this nature, an opinion of the importance of accurate and numerous meteorological observations to have prevailed in many places, especially in Great Britain.

appears recently

We are not aware of there being any complete regular series of observations kept in this country. We know, at least, of no journal in which such a series is registered. It appears to us very desirable that this deficiency should be supplied: and we should willingly hope that an example, fairly held up by this society, would be followed by similar associations in other parts of the United States.

We proceed to an enumeration of those particulars which we consider as the principal desiderata in observations of this nature.

1st. Changes of temperature.

In the choice of a thermometer, as the standard of temperature, great care should be taken that the instrument be well made. The diversity so frequently observable in thermometers under the same exposure, arises principally from the want of a complete expulsion of air from the tube, and from imperfect graduation. For the estimation of sudden changes of temperature, thermometers with cylindrical reservoirs are preferable to those which are globular.

The mean heat of the atmosphere is so easily affected by irregular currents of air through halls, entries, and other situations within the walls of a building, that it is deemed absolutely necessary, in order to arrive at the standard temperature, that the instrument be exposed to the open air, sheltered only from the sun and rain. A situation which we

1

* This paper was read as the report of a committee appointed to consider of the subject to which it relates.

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