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and our mind is enabled to undergo new exertions by its increased activity and the reanimation of all the intellectual faculties.

How culpable are those who, from trifling views, a sordid interest, or the gratification of their passions, deny themselves the necessary portion of sleep! They interrupt the order of nature, which has been established for their good; they destroy their gaiety of heart, enervate their bodily strength, and hasten the short period of their existence by inducing a premature old age. Why should we be so foolish as to deprive ourselves of a blessing which the bountiful favour of Heaven bestows upon all descriptions of men, upon the poor as well as the rich, upon the learned as upon the ignorant? Why should we shorten our days by refusing the gift which nature offers of prolonging our life by the renovating repose of sleep? The nights may come, when, far from enjoying the sweet refreshment of sleep, tossing on the bed of anguish, we shall be counting the tedious hours as they heavily pass over. Few know or estimate the va lue of sleep till they have wished for it in vain; and there are nightly many thousands of human beings who, afflicted with diseases or mental agitation, know not the blessing of this sweet restorer of nature.


Magnitude of the Earth.

To determine the exact size of the earth is attended with considerable difficulty: though there is in fact but one longitude, there are two latitudes, the north and the south, both beginning at the equator; the one extending as far north as the arctic pole, the other south to the antarctic pole. No one has yet been able to penetrate as far as either pole for the mountains of ice in Greenland, and the northern sea, have always impeded on the north; and the south is not more accessible. However, by the labours of geometricians, we are enabled pretty nearly to ascertain the dimensions of our globe; and according to the most exact calculations, the surface of the earth contains 199 mil

lions, 512 thousand, 595 square miles. The seas and unknown parts, by a measurement of the best maps, contain 160 millions, 522 thousand, and 26 square miles; and the inhabited parts 38 millions, 990 thousand, 569 square miles, in the following proportion:-Europe 4 millions, 456 thousand and 65; Asia 10 millions, 768 thousand, 823; Africa 9 millions, 654 thousand, 807; America 14 millions, 110 thousand, 874:* which calculations prove that scarcely a third part of the globe is inhabited.

It has been calculated that there might be at least three thousand millions of men upon the earth at once, whilst in reality there are no more than one thousand and eighty millions; of which there are in Asia 650 millions, in Africa 150, in America 150, and in Europe 130 millions. Supposing then that the earth is inhabited by about one thousand millions, and that thirty-three years make a generation, it would follow that in the above space of time a thousand millions will die; consequently the number of those who die upon the earth amounts each year to 30 millions, every day to about 83,400, every hour to 3475, and every minute to about 57. This calculation is very striking, and will naturally suggest the idea, that since the mortality of each year, and even of each minute, is so great, it is very probable that we may ourselves very soon increase the bills of mortality. At this very instant some one of our fellowcreatures has paid the debt of nature, and ere the lapse of another hour above three thousand more beings will have bid a final adieu to this state of existence. These considerations are awful, and should lead us to the most serious reflections; they should frequently induce us to reflect upon death, and prepare for eternity.

Immense as the earth may appear, its magnitude sinks into nothing when compared with those spheres, which revolve in the heavens; in comparison of the whole system of the universe, it is no more than as a grain of sand is to the most lofty mountain! How this thought raises my conceptions of the inexpressible grandeur of God, the infinite Creator of the heavens and the earth, in comparison of whom this world, and all the worlds we can conceive, with their multiplied inhabitants, are lighter than chaff before the wind, and of less account than the atoms playing in the sun-beams!

*Ferguson's Astronomy.


Generation of Birds.

ABOUT this season of the year nature undergoes a general revolution, highly interesting and well deserving of our attention. This is the time when the joyful birds begin to build their nests and bring forth their tender young; an operation which, though renewed every year, is little regarded.

In each impregnated egg that has not yet been sat upon, a small spot is observed on the yolk, in the centre of which spot is a white circle extending upwards, and appearing to join some small vesicles. In the middle of this circle is a sort of fluid matter, in which swims the embryo of the future chick. It is composed of two lines or white threads, which sometimes appear to be separated from each other at their extremities, and between which a liquid substance is seen of a leaden colour. The extremity of the embryo is contained in a vesicle or small bag, surrounded by a ligament, in which the navel afterward appears. The ligament is partly composed of a solid yellowish matter, and partly of a brown fluid, which is also surrounded by a white circle. These are the chief things observable in an impregnated egg before incubation.

When it has been under the hen about twelve hours, there appears in the lineaments of the embryo a humid matter, which has the form of a little head, and on which vesicles are seen that afterward form the vertebræ of the back. In thirty hours the place of the navel appears covered with a number of little vessels, and the eyes begin to be distinguishable. The two white threads, which in uniting have left still some space between them, enclose five vesicles, which are the matter of the brain and spinal marrow. The heart may next be observed, though it has not been ascer tained whether the heart or the blood is first formed. However this may be, it is certain that the rudiments of the chick existed in the impregnated egg before incubation; and when it has been some time sat on, the vertebræ, the brain, the spinal marrow, the wings, and part of the muscles, may be distinguished before we can perceive the

heart, the blood, and the vessels. In thirty-six hours the navel is covered with a number of vessels, separated from each other by unequal spaces. The essential parts of the chick being thus developed, it continues to grow larger, and the parts become more distinct, till, in about twenty or oneand-twenty days, it is strong enough to break the shell in which it was enclosed.

We owe these discoveries to those naturalists who, by the assistance of the microscope, have hourly watched and remarked the progressive formation and development of the chick. However, notwithstanding all the information we have derived from their observations, there still remain many mysteries which elude the most penetrating researches. How does the embryo gain entrance into the egg? and how does it acquire, by means of heat, which is all that it receives from the hen, life and growth? What power first puts in motion the essential parts of the chick, and what is that vivifying spirit which, penetrating through the shell, stimulates the heart into action? Who has inspired the birds with that instinct which teaches them to continue their species,and inform them their offspring is contained in the egg, upon which they patiently sit and endure every hardship during the period of incubation?

To these questions we can only answer with certainty, that as nothing can be attributed to blind chance, we look for the cause in the wisdom of God, which has ordered that some animals should not arrive at perfection till after they have left the womb of their mother, whilst others remain in it till all their parts are formed; and he who does not discover in the generation of birds the proof of a Superior Being, will perceive it nowhere. O man! spectator of the glorious works of God, adore with me his marvellous wisdom, and see, even in the meanest objects, the impress of his ineffable goodness and power. He has created the birds of the air for thy advantage, pleasure, and nourishment.


Prognostic Signs of the Weather.

WINDS, heat, cold, rain, snow, fogs, drought, and many other changes in the temperature of the air, do not always depend on certain and regular causes. There are, however, some signs in nature which often indicate the kind of weather about to take place. The position of our globe with respect to the sun, which is known to us by the four seasons of the year; the changes of the moon, the period of which can be exactly determined; the influence which these heavenly bodies and the different planets in our system have upon the temperature, the agitation, and the serenity of the air, are immutable, and on them prognostics respecting the weather may be reasonably founded. The consequences drawn from these are less to be contemned, because they are established upon truth and confirmed by experience. From analogy we have a right from the past, under similar circumstances, to judge of the future. It is true, a thousand contingencies may affect the temperature of the air with changes as great as they were unexpected; but we must remember that these accidental circumstances seldom exist for a length of time, and though they may occasion considerable alteration in the ordinary course of the weather, they only remain for a short space, and their operation is very limited whilst, on the contrary, the changes of weather generally follow a certain order, governed by certain rules; and the attentive observer of nature, by comparing the experience of several years, will often be able to foresee them.

We seldom err when we suppose that the north and east winds will bring cold, the south wind heat, and the west rain; and that during the north-west wind it rains in summer and snows in winter. We may also conjecture with probability, that when the morning sky is red, there will be wind or rain in the course of the day; and that a sky tinged with streaks of red in the evening promises fair weather the following day. From the weather of spring we anticipate that of summer: if in the former we expe

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