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images in the presence of the immortal God! If the gentle rivulets that so beautifully irrigate the earth are so pleasing, if a ray of light is so vivifying, how admirable must be the great Source and First Cause of the torrent of the rivers, the Living Fountain of all joy and excellence! how gloriously pre-eminent the Author of the blessed sun, the rays of which only have such great power!

From what we already know of God through his works, we may form some anticipation of the glory of futurity, and prepare with joy and with gladness for the happy moment, when the soul, released from its present dark and inferior abode, shall ascend into the heavens, and enjoy that purity and exaltation, the reward of those who, by the proper use they have made of their time here, are permitted to join the heavenly choir of angels in songs of the throne of the everlasting God.

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Causes of the Vicissitudes of Heat and Cold.

WHAT Occasions the transition from extreme heat to intense cold? By what means does nature effect these vicissitudes? It is certain that in winter the state of temperasure principally depends upon the sun; for when our globe in its annual course round that luminary is so situated that its northern hemisphere is turned away from the sun, when the rays fall obliquely upon the earth's surface, and when the sun remains only a few hours above our horizon, it is impossible that its rays can be so powerful as when they fall more perpendicularly. But the heat does not entirely depend upon the distance and situation of the sun, which annually passes through the same constellations, and is not more distant in one winter than in another, yet the degree of cold varies very much in different winters. Sometimes a great part of the winter is as mild as autumn, whilst in another the deepest rivers are frozen, and men and animals are scarcely preserved from the effects of the cold. Even in those countries where the days and nights, during most part of the year, are of an equal length, the heat of the sun'

is too feeble to melt the ice and the snow on the summit of the mountains. On their heights reigns an eternal winter, whilst at their base verdure flourishes and summer smiles; yet the rays of the sun fall upon their ridge as well as in the valleys. From these circumstances it would seem as if the sun was not the only cause of heat, otherwise these phenomena would be inexplicable.

Nature is rich in resources, and a thousand causes of which we are ignorant may assist her operations. We know that the winds and the atmosphere have a great influence upon the heat and cold of a country. Hence it sometimes happens, that in the midst of summer, when the atmosphere is charged with vapours, the heavens are obscured by thick clouds, and the north wind blows, that great cold is felt; and on the contrary in winter, when the wind is from the south, the temperature is often much milder. The peculiar nature of the soil may have some effect; and the winds blowing over the ocean acquire a higher temperature, which they impart to the earth as they sweep over its surface.

These causes, and, perhaps, many others we do not yet know, influence the temperature of the air, and produce the sudden alternations of heat and cold. In most of our investigations of nature we are obliged to stop short of the truth; and the most able philosophers have not been ashamed to confess how little they knew of her laws. We can comprehend but a very small part of her operations, and no doubt it is from the wisest reasons the Creator has concealed from our penetration the causes of so many ef fects which we view with wonder throughout the kingdom of Nature; but we know enough of them to be happy, wise, and content: let us endeavour to use, with propriety, the little knowledge we are permitted to acquire, and convert it to the advantage of our fellow-creatures, and the glory of God; for surely he did not give us our faculties to be buried in sloth and indolence, nor to be employed in trifling pursuits, or to become obliterated or perverted for want of cultivation and exertion.



Singularities in the Mineral Kingdom.

FROM the limited nature of our understanding, it would be difficult, if not impossible, for us to comprehend, at once, the whole kingdom of nature, and to know and distinguish all the properties and qualities of her productions. We shall be facilitated in our search, and assisted in our inquiry, into nature, if we begin by the consideration of some simple and detached objects, whose beauties will engage our attention, and whose peculiar phenomena will solicit our regard. At present, then, I shall consider some curiosities. met with in the mineral kingdom, amongst which none are more remarkable than the magnet. When suspended, one of its extremities points to the north, the other to the south; these are called its poles, and they seem to contain the magnetic principle in greater abundance than the other parts. It does not appear to attract any other substance than iron, or the ores of iron: if you place the north pole of one magnet opposite the south pole of another, they will be mutually attracted; but if their similar poles, whether the two north or the two south poles, are placed together, they repel each other.

Mercury offers to our consideration properties equally remarkable, and more useful. It is distinguished from all other metals by its fluidity, but it becomes solid when exposed to a sufficient degree of cold. In a heat of 600° it boils, and may be totally evaporated; exposed to the air and agitated, it attracts a portion of oxygen, and is converted

The magnet does not appear to be a stone, as the author has represented, but iron only, or iron contained in stone, modified in such a manner as to admit the passage of the magnetic fluid; of which little is known, though some suppose it to be a modification of the electric power; to support which they assert, that iron long placed in an elevated position becomes magnetic; that instruments of iron struck with lightning are sometimes magnetised, and that two pieces of iron may be magnetised by rubbing them against each other in the same direction. But supposing it was the electric fluid undergoing a peculiar change in the iron, we are still no nearer the moon; for we are equally in the dark respecting the nature of an electric as of a magnetic fluid. It is their effects only with which we are acquainted.-E.

into a powder called oxide, which is black, yellow, and red, according as the oxygen is in greater or less proportion. By the application of heat the oxygen may be extricated from the oxide, and the mercury again assume its original form.

Gold is the most precious and valuable of all metals, not only by its scarcity, but from its admirable properties. No other substance equals it in ductility and malleability. It may be beaten out into leaves so thin that one single grain of solid gold may be made to cover 563 square inches, the leaf being only 2000 part of an inch thick ; and an ounce of gold upon a silver wire is capable of being extended 1300 miles in length. It requires a very strong heat to melt it.

The curious crystals of salt; the peculiar brilliancy of some stones; the great variety of metals; petrified bodies found sometimes in the highest mountains; and a thousand more wonders contained in the mineral kingdom, are well calculated to awaken our curiosity and to excite our astonishment. No pursuit is more gratifying and delightful, or more diversified, than the attentive contemplation of nature. Though we were to live for ages upon the earth, and employed every day and every hour in studying and investigating the phenomena and peculiarities of the mineral kingdom only, there would still remain a thousand things which we could not explain, but which, concealed from our penetration, would still more and more excite our curiosity. Let us then lose no time in entering such a wide field of discovery; let us employ a part of the time we can spare from our indispensable duties and avocations in observing nature, by which our mind will become improved, our knowledge increased, and we shall be rewarded with a very innocent and durable pleasure. The more we meditate upon the designs of God in his works, the more will our sa tisfaction increase, inasmuch as the objects of nature are infinitely more sublime and wonderful than the choicest productions of human genius.

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