What struggles --what tears! And setting aside children, who are by no means always the most disobedient to the will of a good God, how few men would care to stop in the midst of their occupations, to go and grind their teeth one against another for half-an-hour, if there were not some pleasure attached to an exercise not naturally amusing in itself? Ay, ay, my dear child, were it not for the reward in pleasure which is given to men when they eat, the human race, who as a whole do not live too well already, would live still worse. And it is necessary that we should be fed, and well fed too, if we would perform properly here below the mission which we have received from above.

Yes, "reward" was the word I used. Now it seems absurd to you, perhaps, that it should be necessary to reward a man for eating a good dinner? Well, well, God has been more kind to him then, than you would be. To every duty imposed by Him upon man, He has joined a pleasure as a reward for fulfilling it. How many things should I not have to say to you on this subject if you were older? For the present, I will content myself with making a comparison.

When a mother thinks her child is not reasonable enough to do, of her own accord, something which it is nevertheless important she should do, as learning to read, for instance, or to work with her needle, etc., she comes to the rescue with rewards, and gives her a plaything when she has done well. And thus God, who had not confidence enough in man's reason to trust to it alone for supplying the wants of human nature, has placed a plaything in the shape of pleasure after every necessity; and in supplying the want, man finds the reward.

You will hardly believe that what I have here explained to you so quietly by a childish comparison, has been, and alas! still is, the subject of terrible disputes among grown-up people. If hereafter they reach your ears, remember what I have told you now, viz., that the pleasure lodged in the tongue and its surroundings, is a plaything, but a plaything given to us by God; and that we must use it accordingly.

If a little girl has had a plaything given to her by her mother, would she think to please her by breaking it or throwing it into a corner? No, certainly not: she would know that in so doing she would be going directly against her mother's intentions and wishes. Nevertheless she would amuse herself with it in play hours, with an easy conscience, and, if she is amiable, she will remember while she does so, that it comes

to her from her mother, and will thank her at the bottom of her heart.

It is the same with man, of whose playthings we are speaking.

But, moreover, this little girl (it is taken for granted that she is a good little girl) will not make the plaything the business of her whole day, the object of all her thoughts; she will not forget everything for it, she will leave it unhesitatingly when her mamma calls her. Neither will she wish to be alone in her enjoyments, but will gladly see her little friends also enjoy similar playthings, because she thinks that what is good for her must be good for others too.

It is thus that man should do with his playthings; but, alas! this is what he does not by any means always do with them, and hence a great deal has been said against them. Little girls, in particular, are apt to fail on this point, and that is how the dreadful word gluttony came to be invented. For the same reason, also, people get punished from time to time; such punishments being the consequence of the misuse I speak of.

If people who call to see your mamma were, instead of going straight up stairs to her, to establish themselves at the lodge with the porter, and stay there chatting with him, do you think she would be much flattered by their visits? And yet this is exactly what people do who, when eating, attend only to the porter. He is so pleasant, this porter; he says such pretty things to you, that you go on talking to him just as if he were the master of the house, who, meanwhile, has quite gone out of your head.

You heap sugar-plums upon sugar-plums, cakes upon cakes, sweetmeats upon sweetmeats-everything that pleases the porter, but is of no use whatever to the master of the house. And then what happens? The master gets angry sometimes, and no wonder. Mr. Stomach grows weary of these visits, which are of no use to him. He rings all the bells, makes no end of a noise in the house, and forces that traitor of a porter who has engrossed all his company, to do penance. You are ill — your mouth is out of order-you have no appetite for anything. The mamma has taken away the plaything which has been misused, and when she gives it back, there must be great care taken not to do the same thing over again.

I have thought it only right, my dear child, in telling you the history of eating, to give to this little detail of its begin

ning, a place proportioned to your interest in it. You see by what I have said, that you are not altogether wrong in following your taste; but neither must it be forgotten that this part of the business is not in reality the most important; that a plaything is but a plaything, and that the porter is not the master of the house.

Now that we have made our good friend's acquaintance, we will wish him farewell, and I will presently introduce you to his companions of the antechamber, who are ranged on the two sides of the door, to make the toilets for the visitors who present themselves, and to put them in order for being received in the drawing-room. You will see there some jolly little fellows, who are also very useful in their way, and whose history is no less curious. They are called TEETH.

CARBONIC ACID.

WE are going to make acquaintance to-day with a new personage, who well deserves our attention. It is the child of oxygen and carbon, though not in the same way that you are the child of your parents.

To tell you how it is made is more than I am able. It is a gas, or if you like the word better, it is an air; for when we say "gas," we mean "air"; only it is always a different sort of air from the air of the atmosphere, which learned people are not in the habit of calling gas. I cannot, therefore, show you carbonic acid itself, for it cannot be seen any more than the air which fills an empty glass. But I can tell you where there is some, and you even probably know it by its effects, although you have never heard its name.

Do you remember on your aunt's wedding-day, that there was a sparkling wine called champagne, at the grand breakfast? You smile, so I conclude somebody gave you a little to taste; and if so, you will remember how sharp it felt to your tongue. Do you remember, too, how the cork flew out when they were opening the bottle, and how the noise of the "pop!" startled more little girls than one? It was carbonic acid which sent the cork flying in that wild way; the carbonic acid which was imprisoned in the bottle, in desperately close quarters with the wine, and which accordingly flew out, like a regular goblin, the moment the iron wire which held down the cork was removed.

What sparkled in the glass, making that pretty white froth which phizzed so gently, as if inviting you to drink, was the carbonic acid in the wine, making its escape in thousands of tiny bubbles. What felt so sharp to your tongue was the same carbonic acid, in its quality of acidity, for thence it has its name; the word acid being borrowed from a Latin word signifying the sharp pungent taste, almost fine-pointed as it were, peculiar to all substances which we call acids.

It is carbonic acid also which causes the froth in beer and in new wine when bottled. It is he who makes soda-water sparkle and sting the tongue, and ginger-beer the same, if you happen to like it; and so far you have no particular reason for thinking ill of him. But beware. It is with him as with a good many others who have sparkling spirits, who make conversation effervesce with gayety, and who are very seductive in society when you have nothing else to do but to laugh over your glass, but whose society is fatal to the soul which delivers itself up to them. This charming carbonic acid is a mortal poison to any one who allows it to get into his lungs.

You remember what a violent headache your servant suffered from the other day after ironing all those clothes you had in the wash? She owed that headache entirely to this work which she did for you. She had remained too long standing over the coals over which her flat-irons were being heated. You know already that when charcoal burns, it is from the carbon uniting with the oxygen of the air; from this union proceeds that mischievous child, carbonic acid gas, in torrents, and the poor girl was ill, because she had breathed more of this than was good for her health. Observe well, that the room-door was open to let in the fresh air, and that there was a chimney, to allow the carbonic acid to escape. It was on this account that she got off with only a headache. Unhappily, there have sometimes been miserable people who, weary of life, and knowing this, but not knowing or thinking about the God who overrules every sorrow for good, have shut themselves up in a room with a brazier of burning charcoal, after taking the fatal precaution of stopping up every opening by which air could possibly get in; and when at last, in such a case, uneasy friends have forced open the wellclosed door, they have found nothing within but a corpse. Then, too, there are those frightful accidents of which we hear so often, of workmen groping their way down into long disused wells who have died as they reached the bottom; or of sudden deaths

in coal-pits. In general these have been owing to the poor victims encountering the long pent-up carbonic acid gas, whose poisonous breath blasted and destroyed them at once.

You may well ask why I am telling you such horrible stories, and what I am coming to with my carbonic acid? But you have more to do with it than you think, dear child. You and I, and everybody we meet, nay, and the very animals themselves, since their machines are of the same sort as ours, are all little manufactories of carbonic acid. The thing is quite clear. Since there is a charcoal fire lit in every part of our body, there always arises from the union of the oxygen brought by the blood with the carbon it meets in our organs, that mischievous child we have been talking about; and our throat is the chimney by which he gets away. He would kill us outright were he to stop in the house.

This is how it comes about: In proportion as the blood loses its oxygen, it picks up in exchange the carbonic acid produced by combustion, so that it is quite loaded with it by the time it returns to the lungs. There it takes in a fresh supply of oxygen, and discharges at the same time its overplus of carbonic acid, which is driven out of the body by the contractions of the chest, pell-mell with the air which has just been made. use of in breathing. You are aware that this air is not the same at its exit as at its entrance to the body, and that if you try and breathe it over again it will no longer be of the same use to you. That is because it has lost part of its oxygen and brings back to you the carbonic acid which it had just carried off. If you take it in a third time, it will be still worse for you; and in case you should continue to persist — the oxygen always diminishing, and the carbonic acid always increasing in quantity—the air which was at first the means of your life will at last become the cause of your death. Try, as an experiment, to shut yourself up in a small trunk, where no fresh air can get in; or even in a narrow closely-shut closet, and you will soon tell me strange news. There will be no occasion to light a charcoal fire for you in there. Enough is kept burning in your own little stove, and you will poison yourself.

You see now that the dreadful stories I was telling a short time ago have something to do with you, and that it is a good thing to be warned beforehand. And now tell me, when a hundred people-or I ought to say, a hundred manufactories of carbonic acid-are crowded together for a whole evening,