Christ, although these books contain what appear to Christians most remarkable prophecies of Him.

And it was pointed out to you, that there are many parts of these prophecies of which we see the fulfilment before us, though the early Christians did not; namely, that a religion should arise among the Jews, which should have a wide spread among the Gentiles, but yet that it should be a new religion, not the same as taught by Moses; and that this religion should spring, not from the whole nation, but from one individual of that nation, and he a person despised, rejected, and persecuted, even to death, by his own people.

All this, which is so unlike what any one would have foretold from mere guess, and which we see actually come to pass, is prophesied in books which enemies of Christianity (the unbelieving Jews of this day) reverence as divinely inspired.

you,

Now if you reflect attentively on all these heads of evidence which you have been learning, and of which this short summary has just been put before you will perceive that even a portion of it might be fairly considered, as a strong reason to be given of the hope that is in you; but that when you take the whole of it together, it is sufficient to satisfy any reasonable mind; for, to believe that so many marks of truth should be brought together by chance, or by man's contrivance, in favour of a false story,-to believe this, I say, would be much greater credulity than to believe that the Gospel really was from God. These arguments, however, have been laid before you very briefly; and hereafter, if you will study them at leisure, and dwell upon them more fully, in your own mind, and in conversation with others, you

will see the force of them still more and more.

But though these arguments are enough to satisfy you, that an ordinary Christian, who does not pretend to be a learned man, may yet believe in his religion on better grounds than the Pagan has for believing theirs, there are many other arguments -besides, some of which are quite within the reach of the unlearned. In particular, what is called the internal evidence of Christianity, that is, the proof drawn from the character of the religion itself, and of the Christian Scriptures, is a kind of evidence which you will find more and more satisfactory the more you reflect on and study the subject, if you endeavour at the same time sincerely to act up to the knowledge you acquire, and to be the better for it in your life.

MATERNAL SOLICITUDE.-There is something in sickness that breaks down the pride of manhood, that softens the heart, and brings it back to the feelings of infancy. Who that has languished, even in advanced life, in sickness and despondency, who that has pined on a weary bed in the neglect and loneliness of a foreign land, but has thought on the mother that looked on his childhood, that smoothed his pillow, and administered to his helplessness? Oh, there is an endearing tenderness in the love of a mother to a son, that transcends all other affections of the heart! It is neither to be chilled by selfishness, nor daunted by danger, nor weakened by worthlessness, nor stifled by ingratitude. She will sacrifice every comfort to his convenience, she will surrender every pleasure to his enjoyment, she will glory in his fame, exult in his prosperity, and, if adversity overtake him, he will be the dearer to her by misfortune, and if disgrace settle on his name, she will still love and cherish him; and if all the world beside cast him off, she will be all the world to him.-WASHINGTON IRVING.

LET us incessantly bear in mind, that the only thing we have really to be afraid of is fearing anything more than God.-Book of the Fathers.

CARBONIC ACID No. III.

165

IN conformity with the intimation contained in our last paper, we now direct attention to the means which appear to us as specially appointed by the CREATOR for neutralizing, or withdrawing, those gases, and particularly carbonic acid, whose accumulation, beyond certain proportions, would be attended not only with inconvenience but imminent danger. Already has it been remarked, that the quantity of carbonic acid present in the atmosphere is exceedingly variable; it being affected by local situation, by the changes of the seasons, by the alternations of day and night, and by the state of the weather. These variations depend chiefly upon the combined influences of moisture and vegetation; a fact we can best illustrate by referring to the experiments and observations of those who have devoted much of their attention to this interesting branch of philosophic inquiry.

We may just notice, as we pass along, that strictly speaking, air consists of two gases-oxygen and nitrogen-mixed in the proportions of 21 parts of the former with 79 parts of the latter. These gases constitute what might be termed the essential properties of air; but the atmosphere is never in a state of absolute purity; the vapour of water, carbonic acid, and one or two other gases, and the odorous particles of innumerable volatile substances being also present. As respects Carbonic Acid it may appear less difficult to discover its origin than to understand its uses. Its universal diffusion is, however, decisive evidence of design. Those pestilential gases and vapours which prevail only in certain situations, and which are indebted for their existence to sudden changes of weather, to the periodical evaporation and drying up of inland lakes, or rivers, or to the decomposition of vegetable or animal matter, may be viewed as the result of adventitious and partial processes. It is not so with Carbonic Acid. That exists at all times, and in all places, as a component part of the air which envelopes us; and notwithstanding the variations as to quantity, of which we have before spoken, there is no proof that under ordinary circumstances it ever exercises any injurious effects.

A reference to what was stated in a former paper will assist us in understanding how it is that the accumulation of Carbonic Acid beyond certain limits is effectually prevented. We allude to its being absorbed by water. Whilst it is impossible to form any adequate conception of the quantity of this gas which, as the result both of natural and artificial processes, is constantly ascending from the surface of the earth; so is it equally impossible, by any means which fall within the limits of human computation, to estimate the quantity of water suspended in the atmosphere above us. We cannot contemplate a calamity more awful than that which would follow the total cessation of spontaneous evaporation. "No more rain or dew could fall, the springs would cease to flow, the rivers would be dried up; the whole water in the globe would be accumulated in the ocean, and the earth would become dry and parched. Vegetables being deprived of moisture could no longer continue to grow; the cattle and beasts of every kind would lack their usual food; man himself would perish; and the earth would become a dull, inanimate, sterile mass, without any vegetables to embellish its surface, or any living creature to wander through its frightful deserts *."

The vapour of water, and especially that which is the product of spontaneous evaporation, is water in a

· Dr. Thompson.

state of extreme purity. Here we may perceive an additional reason for its being so admirably adapted for the purpose to which we are now alluding; its freedom from all extraneous matter evidently fitting it for uniting the more readily with a gas for which at all times it exhibits a powerful aflinity. There are many natural processes which we are in the habit of designating secret; a term which in this sense implies that the operations in question are of so refined a character that our bodily organs, however they may be assisted by the contrivances of art, are incapable of taking cognizance of them. Thus it is in the instance before us. We know of no means by which to render palpable to the senses the mode in which water and Carbonic Acid unite; but we may satisfy ourselves of the fact in a variety of ways.

It is not so easy to determine whether the gas unites with aqueous vapour, whilst the latter is in a perfect state, that is, previously to its being partially condensed, as when it assumes the form of clouds and mists, but we believe it does. In confirmation of these views, we may mention, that by experiments very carefully conducted, and extending over the space of two years, it was ascertained that air collected at the surface of the earth contained a less proportion of Carbonic Acid than that at the tops of mountains; seeming to indicate that the gas is absorbed most rapidly by newly-formed vapour, and hence its withdrawment takes place exactly where the process is most needed. When wind prevails, the quantity of Carbonic Acid in low situations is augmented, occasioned probably by the mixing of the air from the mountains with that in the valleys. At night, the proportion of this gas is in general greater than during the day, excepting in Winter, when the difference is scarcely perceptible. Here we think we also recognise the influence of evaporation, which is less in Winter than in Summer, and at night is almost, if not entirely, suspended. Rain-water and dew contain Carbonic Acid. Whilst rain continues, the quantity of the gas sensibly diminishes: with the return of dry weather, and particularly at the setting in of frost, it gradually increases. Air taken on the coast, or near the surface of the sea, contains a smaller proportion of Carbonic Acid than that obtained inland; and it is less in every situation when the sun shines, than during dull and cloudy weather. This we have mentioned before; but it is here repeated in order to illustrate, if possible, the principles on which these frequent variations depend.

We must not forget that vegetation is an important auxiliary in removing Carbonic Acid and other noxious gases from the atmosphere. All kinds of plants possess, in a greater or less degree, the power of selecting and appropriating from the soil which surrounds their roots, those materials which are calculated to nourish and promote their growth, and of rejecting whatever would be injurious. In like manner, the leaves of plants resemble a chemical apparatus; for when exposed to the light of the sun, the under sides of the leaves absorb water and Carbonic Acid, both of which substances are rapidly decomposed; and whilst the hydrogen of one and the carbon of the other are retained, and in the sustentation of the plant answers the same purposes that food does to an animal, oxygen is given off at the upper sides of the leaves, and assists in restoring that vital principle to the atmosphere which is so necessary to the support of animated beings.

Returning to the point at which we broke off, we will now endeavour to illustrate; by a reference to one of the most familiar examples, how it is that Carbonic Acid is formed during the process of combustion.

Let us throw upon a brisk fire a moderately-sized lump of coal; noting the progress of what, in common language, is called burning. On its first exposure to heat, the coal, if it be of good quality, will produce a crackling noise; small pieces flying off from its surface, and readily igniting. In a short time, larger pieces will be seen separating from the mass, and from the fractures thus occasioned, a dense, yellowish smoke will issue, which in another minute or less, will be succeeded by flame; and now, combustion having fairly commenced, the smoke will be no longer yellowish, but black. We must still carefully notice what is going on, or some of the most interesting parts of the experiment will escape us.. The coal continuing alternately swelling and cracking, we shall probably perceive at one of the openings a little eminence, like a bubble, forming, until at length a stream of white smoke suddenly bursts from it. In a moment, the smoke inflames, and we have a jet of gas which makes as much noise as if it was projected from the point of a blow-pipe. We must now wait a while. The coal is well kindled, flaming on all sides, and thus it continues to do until it becomes red hot in every part; in that condition, and when in sufficient quantity, constituting what is termed a clear fire. The flame having subsided, our lump of coal rapidly disappears; all that remains of it being a piece or two of cinder, and a few ashes.

The phenomena we have just enumerated, and which occur in less time than is required to write a description of them, comprehend the following processes, namely, vaporization, perfect and imperfect combustion, and decomposition. We propose to say a few words on each of these, which will bring us to the end of the present paper.

The vaporization of fuel always implies waste,—a subject now deemed of so much importance, that the inventions having for their object the economization of coal, are almost numberless. Some of these are of great value; but it is difficult to find one of universal application. A remarkable proof that practical operations cannot always be conducted on purely scientific principles is afforded by the volume of smoke which forms so inconvenient an appendage to the funnel of a steam-vessel. On a moderate computation, not more than one-half the fuel supplied to the furnaces enters into perfect combustion,-a condition essential to its fully exercising its beneficial effects upon the water in the boilers. Vaporization and imperfect combustion are always indicated by smoke; and not only is a waste of fuel a necessary result, but also a waste of heat. In the first instance, the volatile elements of the coal pass off without ignition, and in the second, although they may be ignited, they are so only partially.

Recurring for a moment to our experiment with the lump of coal, we remark, that the yellowishcoloured smoke emitted previous to inflammation, is the result of vaporization. Black smoke accompanies imperfect combustion. The inflammable and heating properties of coal consist of hydrogen and carbon; the latter being in the greatest proportions. Flame is produced by the union of oxygen from the atmosphere with the hydrogen and carbon of the coal, and to effect this union a certain temperature is necessary. Thus, if we throw a piece of coal on a dull fire, and adopt no precautions to insure its ignition, it will smoulder for a time, and then most likely put the fire out. Perfect combustion and decomposition proceed simultaneously; one being a necessary consequence of the other. The instant coal inflames it is a proof that the evaporizing process has ceased; the volatile elements being then con

The

verted into gases. A new order of things now takes place; the hydrogen of the coal combines with oxygen, and produces aqueous vapour (pure water); the carbon of the coal also combines with oxygen, and produces Carbonic Acid. Oxygen, therefore, is a necessary element in the process we are describing, and hence it has received its name—a supporter of combustion. When, as we have already stated, black smoke is present, combustion is incomplete; the supply of oxygen to the burning fuel not being sufficient to combine with all the carbon, a part of which then freely escapes. This is what happens with an oil lamp, or gas-light, when the wick of the former is too high, or too much gas is turned on the latter. A perfectly clear light, and a total absence of smoke, can only be obtained by duly proportioning the supply of the inflammable materials to the quantity of air which can gain access to the burner. elements of nature combine in certain exact proportions; and not in obedience to our capricious wishes. Flame is not essential to perfect combustion; as already adverted to in the case of a clear coal fire, and as may be especially noticed in the burning of charcoal, a practice which, through ignorance, or inadvertence, is often attended by fatal consequences. As charcoal consists almost entirely of carbon, we may readily understand that by its combustion a greater quantity of Carbonic Acid is produced, than from an equal weight of any other kind of fuel. Hence the danger attendant upon its use. Charcoal fires should never be lighted in imperfectly ventilated apartments. It is scarcely safe to do so under any circumstances, excepting in immediate communication with a chimney; instances having occurred in which the Carbonic Acid gas has flowed from one room to another; the unconscious occupants narrowly escaping suffocation.

--

To sleep in a room in which charcoal is, or has been recently, burning, is an act of self-destruction. Let it not be forgotten that the noxious gas proceeding from it, is much heavier than air, and as it cools, therefore, it acccumulates on the floor. Hence it may happen, that a person standing, or even sitting, in a room under the circumstances mentioned, may be tolerably secure, but when he lies down, death is inevitable.

THE aim of education should be to teach us rather how to think than what to think;-rather to improve our minds, so as to enable us to think for ourselves, than to load the memory with the thoughts of others.-BEATTIE.

THE great end of prudence is to give cheerfulness to those hours which splendour cannot gild, and acclamation cannot exhilarate. Those soft intervals of unbended amusement, in which a man shrinks to his natural dimensions, and throws aside the ornaments and disguises which he feels, in privacy, to be useless encumbrances, and to lose all effect when they become familiar. To be happy at home is the ultimate result of all ambition, the end to which every enterprise and labour tends, and of which every desire prompts the execution. It is, indeed, at home that every man must be known by those who would make a just estimate of his virtue or felicity; for smiles and embroidery are alike occasional, and the mind is often dressed for show in painted honour and fictitious benevolence.-JOHNSON.

If a man were only to deal in the world for a day, and should never have occasion to converse more with mankind, never more need their good opinion or good word, it were then no great matter (speaking as to the concernments of this world), if a man spent his reputation all at once, and ventured it at one throw; but if he be to continue in the world, and would have the advantage of conversation while he is in it, let him make use of truth and sincerity in all his words and actions; for nothing but this will last and hold out to the end.-TILLOTSON.

THE HOMEWARD BOUND MARINER. BENEATH a beaming star-lit sky the Ocean bright was spread, And softly o'er its bosom calm the murmuring breezes sped; Deep stillness was on all that night, and rock and mountain lay In mellowed beauty shadowed on many a glassy bay.

And silently and beautiful the waters round her curled,
As, like some giant phantom in the solitude of night, [light,

Unmoved, the ship lay on the deep, for every sail was furled,

fast.

Her tall and solitary form reposed beneath the moonbeams'
Deep stillness was around her on the midnight Ocean's breast,
For all her busy mariners had laid them down to rest; [past,
And many thoughts and many dreams of joys and sorrows
Bright hope-awakened visions to their minds were crowding
I stood alone upon the deck, and, on the midnight sky
I watched the silver-tinted clouds, as they were wandering by:
A scattered and a changeful train, as were the thoughts that
So wildly and so fearfully upon my anxious breast. [pressed
For many a year my path had been upon the Ocean's breast,
Tost like a storm-uprooted weed, without a place of rest:
Peril and Famine had been mine, and every change of woe
That on a wild and stormy deep the mariner must know.
Of brothers three that, full of hope, had left with me their
home,

Rejoicing in youth's glowing strength, the waters wide to roam,
One I had seen a bloody corse when victory was won,
Another died at Fever's touch, beneath the southern sun;

That morn the younger one had found a cold and wavy bed, And now I looked upon the hills for which he languished. A severed and a sorrowing thing, I had come back alone, One wandering bird unto the nest from which a brood had

flown.

light,

And leaves it dark and desolate to tell of Winter's blight.
I feared the morn-I feared to seek my long, long-wished-
As with a sad foreboding dread of misery to come; [for home,
I feared to see my mother's tears, my father's agony,
When they knew that their beloved ones were in the deep,
deep sea.

And, half unconsciously, I watched the pallid moonbeams glide
Yet still my eyes looked wistfully across the ocean-tide,
In silver streams across the hills, until they rested where
The old church raised its ivy-tower upon the midnight air.

I knew that dark green ivy-tower, I knew the house of God, To which so oft in sinless joy my boyhood's steps had trod; Where youth's first breath of prayer and praise had risen up on high,

Pure as the dew-drop of the morn exhaled to the sky.
And many of my early loved were sleeping all around
Within their narrow, silent home, beneath that holy ground;
And on their peaceful resting-place I saw the moonbeams shed
A ray, as if Time's finger pale was pointing to the dead.

I gazed upon the moonbeam pale, till, to my aching eyes,
A melancholy spectral shade seemed on the air to rise;
The phantom of a waking dream with coming sorrow fraught,
The dim ideal shadow of an agonizing thought.

As gliding from my aching sight, the wan, pale figure passed, A damp and painful chilliness o'er my trembling limbs was

cast:

PHILOSOPHY can add to our happiness in no other manner but by diminishing our misery; it should not pretend to increase our present stock, but make us economists of what we are possessed of. The great source of calamity lies in regret or anticipation; he, therefore, is most wise who thinks of the present alone, regardless of the past or future. This is impossible to a man of pleasure; it is difficult to the man of business, and is, in some degree, attainable by the philosopher. Happy were we all born philosophers, all born with a talent of thus dissipating our own cares by spreading them upon all mankind.-GOLDSMITH.

shows the jaws and teeth of a lion; here we find, in the front, sharp and strong cutting teeth to divide their food; on each side of which are one pair of strong, sharp-pointed, conical, canine, or dog teeth, excellently adapted for the purpose of tearing their prey, when dead, or of holding it fast during the last struggle; behind these, on each side, are the grinders, strong, and covered with numerous sharp-pointed prominences. In the bat, on the other hand, the teeth are small, and very numerous, and the grinders are covered with many projecting points, extremely sharp and pointed. The bats feed on insects; it was not necessary, therefore, that their teeth should possess any considerable strength, but although their powerless prey is easily captured, it required a peculiar formation of these organs to enable them to secure their food, and the sharp points on the grinders are, in this case, of great assistance in impaling their tiny victims. In looking through the ranks of all the animal feeders, we shall find the same care bestowed on the necessities of each.

The anteaters, and some few other genera of the Edentata, are entirely destitute of teeth, and secure their prey, which they Fig. 2. swallow whole, by means of their long tongue, to the glutinous surface of which the insects adhere. Fig. 2 is the scull of the great anteater, Aimwollige

The vegetable feeders have their teeth very differ ently formed and arranged; the real canine teeth are entirely wanting, and, in general, the place in which teeth of any description; in the animals which chew they are usually found is left entirely destitute of the cud, as the ox, sheep, &c., the cutting teeth are only found in the lower jaw, their place in the front of the upper jaw being supplied by a kind of gristly pad; this is not the case with the horse, which equally with the sheep feeds upon grass, but it does not chew the cud. This different enables the sheep, ser, nt arrangement of the teeth than the horse. The sheep, the goat, and others of &c., to grass much closer the same order, that is, ruminants, frequent the sides of mountains, spacious downs, and other places in which the herbage is stunted, while the horse, on the other hand, is found in countries where vegetable nature is more luxuriant and abundant.

Another order of vegetable feeders instead of living the branches of trees, nuts, and hard roots; in these, upon soft substances, are indebted for their existence to we find the front teeth enormously strong and trenchant, as in the beaver, the squirrel, the marmot, and the rat. Now these strong cutting teeth are constantly losing their substance by the frequent act of gnawing. This would naturally soon wear them down, even to the gums, but Providence, to provide

against this event, has formed these teeth unlike those of any other description; instead of being formed i the first instance as they are to remain through life, that is, like a solid bone, the lower end or root of the teeth of the gnawing animals is embedded in a kind of pulp, from which the bony part of the tooth is formed, so that, as fast as the cutting end worn down, fresh bone is formed at the root, and the tooth itself pushed upwards; and this is so constantly going on, that if the opposing tooth, say in the upper jaw, is lost, that in the lower will continue to grow, until it will at last, forming a curve, reach the inner part of the mouth, as in fig. 4; this is not uncommonly seen in the heads of wild rabbits and hares. The beaver, whose habits require the con-o stant use of these cutting teeth, hasig them in the greatest perfection. With respect to the grinding teeth of these last vegetable feeders, we find their surfaces flat, and fitted for reducing their food to a pulpy mass; to assist them in this operation, the articulation of the jaws is so managed as to allow them a considerable lateral motion. This flattened form of the grinding teeth is most conspicuous in the elephant, in which animal the substance of the tooth is formed of concentric layers of bone and ivory.T

IN benevolent natures, the impulses to pity is so sudden, that, like instruments of music which obey the touch, the objects which are fitted to excite such impressions, work so instantaneous an effect, that you would think the will was scarce concerned, and that the mind was altogether passive in the sympathy which her own goodness has excited. The up, and wholly engrossed by the object of pity, that she truth is, the soul, generally in such cases, is so busily taken does not attend to her own operations, or take leisure to examine the principles upon which she acts.-STERNE

org LONDON:eods of betimil set JOHN WILLIAM PARKER, WEST STRAND. PUBLISHED IN WEEKLY NUMBERS, PRICE ONE PENNY, AND IN MONTHLY PARTS edt Al Move 1S PRICE SIXPENCE. teom od