A. It furnishes a covering for corn and other vegetables: by which they are guarded from the intense cold of the air; especially, from piercing winds and hard frosts. It also prevents the internal heat of the earth from escaping; and, when melting, it moistens and pulverizes the soil, which had been bound up by the frost; and thereby promotes vegetation.

OF RAIN.

Q. What is rain:

A. A precipitated cloud, descending in the form of drops of water; or, snow, dissolved in passing through the lower and warmer region of the atmosphere. Rain, therefore, has its origin in regions below those of snow and hail.

Q. How do you account for the various sizes of drops of rain?

A. On mountains, drops of rain as well as flakes of snow, and hailstones, are very small; and the more intense the clectricity is that forms them, the larger they are. Their bulk is also increased from the length of their descent through a bumid atmosphere; by attracting particles of vapour as they fall: for, it is known, that a vessel placed on the top of a high tower, will not collect so much rain, as another of the same dincnsions, set on the ground.

Q. What are the chief uses of rain?

A. It moistens and softens the earth, and, thus, fits it for affording nourishment to plants. By falling on mountains, it carries down with it many particles of loose earth, which serve to fertilize the surrounding valleys: it purifies the air from noxious exhalations, which tend, in the preturn to the earth, to meliorate the soil: it moderates the heat of the air: and it is one means of supplying fountains and rivers. It is supposed, there was no rain before the Flood, but that the earth was moistened by plentiful dews or mists: of course, there could have been then no rain-bow; a meteor recorded in the Bible as appearing, for the first time, after that great occurrence.

OF FOG AND DEW.

Q. What is fog?

A. Fog or mist, is a meteor, consisting of gross vapours, floating near the surface of the earth.

Q. How is it formed?

A. By vapours raised from the earth, which meet, at their first entrance into the atmosphere, with cold, sufficient to condense them considerably: their specific gravity being thus increased, their ascent is stopped at some particular height, and they either remain suspended for some time, or return back in a kind of drizzly rain.

When these vapours are very light and subtle, and become condensed by the coldness of the night before they arrive at any considerable height, they return back in imperceptible drops; and form what is called dew.

Fogs are only low clouds, or clouds in the lowest region of the air; and clouds are nothing more than fogs raised on high.

OF WATER SPOUTS.

Q. What is a water spout?

A. It is a large column of water, rising in a spiral form from the agitated ocean, with a frightful rushing noise, to a vast height in the air.

Q. What is the cause of this phenomenon?

A. Dr. Franklin ascribes it to the same cause which produces whirlwinds; namely, the rarefaction of the air; an hypothesis which is strengthened by its seldu appearing except in warm climates.

Q. D) water spouts often occur?

A. Yes, in the vicinity of the equator they are yery frequent, and would often, e danger or destroy ships, were not ineans found to reduce them before their very near approach. A water spout is readily destroyed by firing a cannon: the pressure of the surrounding air is thus decreased, by rarefaction, and, consequently, it is expanded, and falls upon the ocean in the manner of a heavy shower.

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OF EARTAQUAKES.

Q. What is an earthquake?

A. A tremendous agitation of some considerable part of the earth, attended with a noise like thun. der; and frequently with an eruption of wind or smoke, water or fire. It is, undoubtedly, the greatest and most formidable phenomenon of nature.

Q. Whence, the cause of these terrible phenomena?

A. Phose of a superficial kind may have an electric origin: for, when a part of the earth is in a highly electrified state, the approach of a non-electric cloud will produce a sudden discharge, and occasion a violent corimotion in the earth, many miles in compass. The principal agent of those that are interior and more tremedous, is subterane

ous fire.

Q. Please to explain those of subterraneous origin?

A. The earth abounds with subteraneous caverns, canals, and veins; some full of exhalations; others, full of water; and some parts replete with nitre, sulphur, bitumen, &c. which produce fire: hence, it is easy

to conceive the terrible effects which may be occasioned from such confined air or water, when acted upon and greatly rarefied hy fire; espe.

cially, if it be considered, that the expansive force of steam is twenty-eight times greater than the force of gunpowder.

OF VOLOANOES.

Q. What are voleanoes?

A. Volcanoes are burning mountains, which emit flame, ashes, cinders, stones, liquid sulphur, and other substances. There are many of them dispersed in all the quarters of the world: the principal of those in Europe, are Etna, or Gibel, in Sicily: Vesuvius, in Naples; and Hecla, in Iceland. It is owing to those vents of subterraneous fires, that the effects of earthquake are not more frequent and dreadful.

ON THE TIDES.

Q. What are meant by the tides?

A. Two periodical motions of the waters of the sea; called the flux and reflux, or the low and ebb.

Q. Please to explain these motions?

A. The sea is observed to flow from the equator towards the north and the south pole, for about six hours; in which motion, or flux, the sea gradually swells: so that, entering the mouths of rivers, it drives back the river waters towards their source.

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