FEB. XXIII.

Causes of Heat and Cold.

WHAT occasions the transition from excessive heat to the severest cold? By what means does nature work these changes? It is not to be doubted, that, during the winter, the temperature depends on the situation of the sun. For, wheu our globe, in its annual course round the sun, is placed so that its northern hemisphere turns from it; when the rays fall very obliquely upon our countries, and when the sun is but a few hours above our hori. zon, it is not possible its rays should give warmth. But the heat does not entirely depend on the situa tion and distance of the sun, which runs over the same constellations every year, and is not farther from us one year than another; yet, the degrees of cold in our winters differ very much. Some winters are as mild as antumn, and in others, deep seas are frozen, and men and animals can scarce protect themselves from the cold. Even in the countries where, most of the year, the days and nights are of equal length, the power of the sun is too weak to melt the ice on the tops of the mountains. The severest winter reigns at their summit, and the hottest summer in the valleys, though the same rays fall equally on hoth places. If the sun was the only cause of heat and cold, these phenomena would be unaccountable. Nature is rich in means; and a thousand causes, unknown perhaps to us, second its operations. But we know, at least, that the nature of the air and the winds have great influence, in regard to the heat and cold of a country. From thence it often happens to be cold in the longest days of summer, when the atmosphere is loaded with vapours, and the sky has been long darkened with clouds, or when the sharp north wind blows strong. From

thence it happens also, that in winter the cold is not severe, when the southerly winds bring us warm air. The nature even of the soil contributes to heat or cold. In Siberia, for example, where the ground is full of saltpetre, and other salts, it is always colder than in countries nearer the pole, and where the rays of the sun are more oblique. The heat of the earth itself, and its interior heat, cause also a difference of heat and cold in the soil of certain countries.

These causes, and perhaps many others unknown to us, occasion the changes of heat and cold upon the earth. But who can know all the springs of the great machine of the universe, or explain their different effects? Most of the phenomena puzzle and confound us; and we are obliged to confess that all the sagacity of the greatest philosophers does not enable them to penetrate into the depths of nature. We see but a part, and undoubtedly the smallest part, of her operations. And certainly it is for very wise reasons that the Creator has concealed from us the causes of so many effects which we see in the course of nature and his providence. He meant by this to teach us to look into ourselves. What use, in ́reality, would the most perfect knowledge of nature be to us, if we neglected to rectify, and be acquainted with our own hearts? We know enough of it to teach us wisdom and content. Perhaps a greater knowledge of nature would make us vain. Perhaps it would disturb our rest, and make us forget God. Let us endeavour only to make a good use of the little we know, by be. coming better; and thus glorifying the Supreme Being. If after all our inquiries and reflections, there still remain many things concealed from us, let us from thence draw this natural conclu. sion, That the wisdom of God surpasses all our conceptions, and that it is infinite: that our understandings are limited; and therefore, with a

proper sense of our weakness and incapacity, our great duty is to humble ourselves, and adore the Most High God.

FEB. XXIV.

Singularities in the Kingdom of Minerals.

IT would be difficult, if not impossible, for our weak and limited understandings, to take in at once the whole kingdom of nature, and to learn altogether the wonderful properties of things. We shall more easily obtain a knowledge of nature, if we begin by some separate objects, some particular beauties, and dwell first on the most striking phenomena. Let us then, at present, reflect on some curiosities among minerals. We shall discover there, as every where else, traces of the infinite wisdom of God. Amongst these there are few more worthy our attention than the loadstone. When this stone is suspended, it turns itself constantly, one end towards the north, and the other towards the south; and it is in those two ends, or poles, that it has the strongest power of attraction. It is remarkable, that it attracts nothing but iron; and that, if two loadstones are put together, their poles of different denomination, that is to say, the southern and northern pole, attract one another; whereas, the poles of the same name, that is to say, the two southern, or the two northern, repel one another, and seem to fly from each other.

There are two properties found in quicksilver equally wonderful. It takes every form one wishes to give it; but it always ends by re-assuming its own natural form. In the fire it rises into vapour. When it is shaken a long time, it changes into dust. By being dissolved, it becomes a hard and transparent chrystal; but it can always be

restored to its former fluid state. Gold is the first and most valuable of all metals, not only from its scarcity, but from its admirable properties. It is the hardest and most unalterable of all bodies. It can bear, for two months, being in the hottest fire, without any sensible loss in its weight. Its parts are so fine, that a grain of beaten gold can cover fifty square inches, in such a manner that the naked eye may distinguish, on the two surfaces, four millions of particles; and its ductility is such, that, with a single grain, one may draw out a thread five hundred feet long. The wonderful form of common salt; the brilliant stones; the singular figures of the earth, where the metals are concealed, the petrified bodies that are often found on the high mountains, some hundred miles from the sea, which is their original source; and an hundred other singularities in the mineral world, seem formed to awaken our curiosity. No em ployment whatever has more charms, is more satisfactory, or has more variety in it, than an attentive observation of nature. Supposing we were to live ages on the earth, and that we were to employ every day, every hour, in studying only the singularities amongst minerals, there would still be, at the end of that time, a thousand things we could not explain, which would remain hidden from us, and would more and more raise our curiosity. Since our lives scarce extend to half an age, let us then make good use of the little time granted us; and let us devote it, as much as our first duties will permit, to the observation of nature; and thus enjoy the most innocent and lasting pleasures of the mind. The satisfaction we shall find in it will increase more and more, in proportion as we reflect more attentively on the views God has proposed to himself in his works: for the wonders of nature are infinitely more to be admired, and more sublime, than alt the productions of human art. The latter do not

always promote our welfare, or make us better: they are often mere objects of fruitless admiration. But all the works of nature, and even the most singular among them, tend to the universal good of the world. They exist, not only to be seen, but also to be enjoyed; and all, without exception, proclaim the goodness, as well as the wisdom of God.

FEB. XXV.

Daily Proofs experienced of Divine Providence.

LET us try to enumerate all the blessings which the mercy of God has heaped upon us, from the first moment of our existence to the present hour. Could we reckon the stars, we could as little think of numbering the blessings we have received during the course of one year only. What would it be, then, during the course, perhaps, of a long life? What mercies received during our infancy, though they are now forgotten? nights passed quietly in a sound sleep; food that nourished and strengthened us. From how many visible and invisible dangers have we not been delivered? How often has God provided for our necessities, and confounded our incredulity, when we thought it impossible? Nothing can happen to us from which the eye of Heaven cannot save us. Every day of our lives has increased the number of God's mercies. Each time the sun begins his course, his goodness is renewed towards us. And who knows how often God has shewn his mercy, and preserved us from dangers unknown to us, and with which we shall only be acquainted in the world to come? What shall we then say of the blessings of the Lord, in having redeemed us, through Jesus Christ; in having given us the gos pel, to teach us the way to salvation? What mercy, that we were not born in the darkness of