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BAROMETER AND THERMOMETER DIFFER.

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It is generally supposed that a high barometer is dependent upon a cold and somewhat dry dense atmosphere, and in proportion to the height of the barometer is the volume of cold air, or its intensity, etc. A low barometer, therefore, is connected with a warm and moist atmosphere, either in volume or intensity. Hence the barometer and the thermometer are, as respects their indications, opposed to each other. A high barometer and low thermometer, a low barometer and high thermometer, are natural associates. But this rule is not observed, or, at any rate, is not indicated by the instruments, which we perceive, by the table already given, very rarely accord. There is, therefore, a discrepancy and an anomaly. Whatever theory or view we adopt we shall meet with the same difficulty, for the consecutive series present no appearance of order, except the mere order of time of succession.

We therefore are compelled to adopt the view of Professor Faraday, and have every reason to believe it to be perfectly consonant to nature, and adequate to the full explanation of all the complex and diverse cases. The table from November, 1813, to December, 1814, a period of fourteen months, gives only one instance in which the barometer and thermometer acted in unison, and simultaneously, or on the same day. On 29th January the barometer was lowest for the month, and the thermometer highest. However delicately the barometer in its horary or diurnal oscillations in the tropics may follow the variations of temperature, it is evident, from the consecutive series, that no such state

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DIFFERENCE OF TEMPERATURE.

obtains in our own climate-there is a wide disparity of action, and no concord. We are, therefore, inclined to suppose that as great fluctuations of temperature take place in the upper regions of our atmosphere as below; but that in the tropics the same general equanimity, and uniform temperature exists in the upper strata as prevails in the lower.

In our own climate it may be cold below and comparatively warm above, or warm below and relatively cold above, and these conflicting strata act in the mass upon the barometer, which represents the absolute weight of the whole column of the atmosphere, whatever be its height, density, or temperature. Whereas the little delicate thermometer merely records the state of the medium in which it is placed. The atmosphere in the temperate and polar regions differs, in some degree, from the tropics, in its laws and actions. The year 1814 is distinguished from all in the present century, from 1800 to 1857, by being the only one which has enjoyed the celebrity of a fair upon the Thames in consequence of the protracted severity of the winter. As these fairs are happily of a rare occurrence, a few observations are not irrelevant to our subject, especially as the mere epitome of the meteorological register would not convey any adequate or correct idea.

A little detail serves to enliven the matter, and illustrates in a very pleasing and instructive manner an important natural and national epoch. In the list of these frost fairs upon the Thames there is one uniform fact, that they all terminated early in February, as 6th

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or 8th-that, for the most part, they began on the first week of December, or with preparatory signs in November, and lasted generally about from eight to ten weeks.

1683-4. Severe Frost from beginning of December to 6th February; an ox roasted on the ice; a whole town erected on the Thames, streets, shops, etc. Coaches plied on the Thames ; bull baiting, horse racing, Bacchanalian triumph and a grand carnival. Charles II. and his court visited the fair. On February 6th, the day after the breaking up of the frost, Charles II. died, and James II. was proclaimed.

1688-9. A great frost from December 20th to February 6th, coaches and waggons plied regularly on the Thames, the ice 18 inches thick.

1715. A large frost fair on the Thames. Frost from November 10 to February 9.

1739-40. A frost fair, ox roasted, printing presses. 1789. January 8th. The Thames frozen, and a great fair was held; booths, shows, wild beasts, bear-hunt, etc.; the frost lasted six weeks.

1814 is the last frost fair, and of which we propose to give some particulars, which may be regarded as the type and exemplification of the preceding ones, and in all probability of any and all succeeding ones. So little does nature or man vary that one account will suffice for all.

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FROST FAIR OF 1814.

THE GREAT FROST AND FAIR ON THE THAMES, 1814.

We perceive by the Epitome which we have given that the highest barometer was on the 26th December, 1813, which denoted the accession of a lofty body of cold air, which produced a precipitation of the vapour of the lower regions, and occasioned a most prodigious dense fog, so that the darkness of the day was as that of night -especially in London. All pedestrians carried links or lanterns; horses in coaches were obliged to be led. This fog was so black and thick as almost to be felt. It was a horrid London dry fog, and continued until the night of the 31st, when a light breeze from N.E., and increasing cold and dryness of the air, dispersed it.

But January began with light mists, more or less every day, which rendered travelling extremely dangerous, and the air was loaded with frozen particles, which attaching themselves to all objects, covered them with rime, or beautiful and delicate crystals; the trees and shrubs were completely coated, and had a most elegant and picturesque appearance, the twigs seeming like white coral. The evergreens were absolutely encased in ice, as if they were in transparent varnish, and the loftiest trees appeared grand and magnificent objects in this new livery, and the whole of nature was dressed in a variety of exquisite devices of frost work, which was the admiration of all beholders. But at length the sun broke out and loosened the rime, which fell unmelted, and lay upon the ground in large

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DETAIL OF THE FROST.

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heaps under the trees; after which a deep snow, brought by an easterly wind on the 4th of January, reduced the whole scene to the more ordinary appearance of our winter.

4th, 5th, and 6th. The snow continued falling, more or less, and presented an amusing phenomenon; for instead of driving loose before the wind, it collected occasionally into little balls, which were rolled along the ground by the wind, till the increasing weight and bulk stopped it. Thousands of these natural snow balls were seen lying about in the fields, some of them being several inches in diameter. The snow fell continuously for 48 hours.

On the 9th of January the thermometer in the snow at night was as low as 5, and the air 8°. Barometer 29.3. The frost continued steady with a day temperature of about 30°, and the night temperature 20°.

On the 12th of January the river Lea was completely frozen over, and the Thames was much encumbered with ice; the ponds and rivers were all frozen. Trade in all the streets was nearly stopped; few carriages or coaches could now travel. Immense icicles were suspended from all the buildings, the water pipes frozen, etc.

Skating was pursued with avidity; ladies robed in the richest furs frequented the Serpentine and performed reels, dances, and quadrilles with the utmost elegance and precision, and made various devices and figures on the ice, and carved out the letters of the alphabet and words.

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