still be necessary to account for the medicinal virtue of these baths. The most simple cause we can give is this, that the waters, passing through grounds mixed with sulphur, fire-stones, and metals, acquire this degree of heat. When the water falls on those quarries, the sulphureous and ferruginous particles which it dissolves, heat and take fire by the friction and re-action of their principles, and communicate this heat to the water. Medicinal waters, particularly the acids, are produced by the dissolving and mixing with the minerals they wash away. They are found particularly in places where there is abundance of iron, copper, sulphur, or charcoal. This is the reason there is such difference both in the effect and taste of them, în proportion as they are more or less mixed with either of these substances. They are bitter when they are produced by bitter roots, saltpetre, or copper. They are cold when they come out of rocks, or are impregnated with sal ammoniac, saltpetre, alum, &c. Oily and bituminous substances make them oleaginous; brimstone mixed with acids makes them sulphureous.

Let us admire the Divine Goodness, which has prepared for man those salutary and inexhaustible springs. Mineral waters may certainly answer many other purposes; but it cannot be doubted they were also produced for the preservation of the health of mankind. It is for man that the Lord has made these beneficent waters to spring up. Let us then acknowledge his goodness, and be sensibly touched with it. Those, particularly, who experience their strengthening and salutary virtue, let their souls, penetrated with joy and gratitude, be lifted up to their Heavenly Father. Let them glorify him, by imitating his example; and let their riches be sources of life and consolation to their fellow-creatures in necessity.

A

LESSON LXXXI.

The Twilight.

Ir cannot be doubted that this phenomenon which we daily behold, is equally with the rest designed for our benefit. The twilight is nothing more than a prolongation of day, which prepares our eyes sometimes to bear the full light, and at other times the darkness of the night. But twilights are not always the same: they vary according to seasons and climates. Towards the poles they last longer than in the torrid zone. The people of that zone behold the sun rise directly above their horizon, and sink down in the same direction under the lower hemisphere; by which means they are left all at once in total darkness. On the contrary, the sun reflecting its rays obliquely towards the poles, and not sinking much below the horizon of the neighbouring people, their nights, though long, are almost all along attended with twilight, therefore not dark. It is a happiness for the former to have scarcely any twilight, and for the others to have an almost constant dawn. As for us, who are placed nearly at an equal distance from the torrid and frigid zone, we plainly observe that our twilights become shorter in proportion as the days shorten, and that they increase as the days lengthen. We enjoy day-light an hour or more after the sun has set. The twilight is equally long before the sur rises above the horizon. We owe this useful circumstance to the properties of the air. God hath surrounded the earth with an atmosphere, which rises very high. He formed such proportion between this air and the light which comes upon it, than when it enters directly down into it, nothing can obstruct its course; but when a ray enters sideways, or obliquely, into this air, the ray, instead of passing

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through the air in a direct line, bends or descends a little lower; so that most of the rays which pierce the atmosphere alongside of the earth, fall again, by means of this inflection, upon the earth. Instead of following their course in passing by the side, they are bent by the air and directed towards the earth. Thus, when the sun approaches our horizon, many of its rays which pass by us, vand are not sent towards us, meet the mass of air which surrounds us, and bending in that mass they reach our eyes; so that we see day-light long before the sun itself appears. This refraction of light in the body of air which surrounds us, is a work equally full of wisdom and goodness for all the people of the earth; but it is a particular blessing to those who inhabit the frigid zones. They would be in darkness for several months together, if they had no twilight. Perhaps this explanation of the origin of twilights may not be intelligible to every reader; but let us leave to philosophers a further detail of it, and limit ourselves to reflecting on it as reasonable beings.

The honest, though ignorant Christian, may possibly be wiser than many philosophers; who, while they explain and calculate the twilights, lose sight of that great Being who gives to man the light of dayan alley, has syab oft mai

sde 10 2500 23 Jula garab, ramrody?

Difference of Zones; i. e. Girdles or Divisions of the Earth.

THE Creator having made our earth in the form of a globe, and impressed upon it a double motion, it necessarily followed, that the regions of the earth must be different from each other; not only in re

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spect to the temperature of the air, and the seasons, but to the animals and plants also. In certain countries there is but one season; the summer is continual there, and every day is as hot as our summer days. Those countries are situated in the middle of the globe, and occupy the space called the Torrid Zone. The finest and richest fruits which nature produces, grow there; and it is there in general where she most liberally pours forth her treasures. The days and nights are of equal length most of the year. There are, on the contrary, countries, where during the greatest part of the year it is colder than our severest winters. It is but a few weeks in the year warm enough for the few trees and herbs which are there, to grow or become green; and in those frigid zones, neither the trees nor the earth produce fruit which mankind could feed on. The greatest inequality of day and night is there: each of them last, in their turn, for whole months together. The two temperate zones, placed between the torrid and the frozen, occupy the greatest part of our globe. In those countries, four seasons appear, more or less distinctly, according as they approach the torrid, or the frigid zone. The spring, wherein the trees and plants bud and blossom, the heat is moderate, and the days and nights nearly equal. The summer, during which the fruits of the field and trees ripen, when the heat is more intense, and the days become visibly longer than the nights. The autumn, when the fruit and the seeds fall off, and the grass withers, while the night again becomes equal with the day, and the heat is daily abating. The winter, during which the vegetation of plants totally or partly ceases, the nights lengthen, and the cold more or less increases.

The countries of the temperate zones are so situated, that in those which are near one of the sides of the torrid zone, the seasons are directly contrary to those of the other temperate zone. When it is

summer in one, it is winter in the other, &c. In these parts, nature shows more variety in the produce of the earth, and in animals, than elsewhere. Wine is peculiar to these countries; for the vine cannot be cultivated either in intensely hot, or severely cold climates. Mankind in particular have advantages under such climates. However varied the regions of our earth may be, the Creator has provided for the happiness of all who inhabit them. He ordains that each country should produce what is 1.most requisite, according to the nature of the climate. A worm, which feeds on the leaves of the mulberrytree, spins for the people of the torrid zone a web, from which they take silk for their clothing. A tree, as well as a shrub, bears a kind of husk or shell full of fine cotton wool, with which light clothing is easily made. The cold regions abound with quadrupeds, the skins of which serve for clothing to the inhabitants of the north; and they are furnished with thick forests, which supply them with abundance of fuel. That the blood of the inhabitants of the warm climates, naturally heated, may not be too much inflamed, their fields and orchards give them cooling fruits, in such plenty, that they may send ample provision of them to other countries. In cold climates, the great quantity of fish contained in the sea and lakes, and the number of animals they have, supply the place of fruit. Thus, there is no region in our globe, that does not feel the greatness and goodness of the Almighty. There is no country, however barren and poor we may suppose it, where nature is not bountiful enough to provide, not only the necessaries, but the comforts of life.