William S. Walsh

“ Monsieur Roger continued:
"By much reflection, by hard work and calculation, Newton made an admirable discovery,—that of universal attraction. Yes, he discovered that all bodies, different though they may be, attract each other: they draw towards each other; the bodies which occupy the celestial spaces,—planets and suns,—as well as the bodies which are found upon our earth. The force which attracts bodies towards the earth, which made this stone fall, as Newton's apple fell, has received the name of weight. ”

“ Monsieur Roger smiled.
"You are wrong," replied Monsieur Dalize, "to excuse by your smile Paul's indifference to the sciences.—And as to you, Paul, you would do well to take as your example Monsieur Roger, who would not have his fortune if he had not known chemistry and the physical sciences. In our day the sciences are indispensable."
Miss Miette, who had shoved herself a little away from the table, pouting slightly, heard these words, and came to the defence of the one whom she had begun by attacking. ”

“ There are certain compounds containing nitrogen which are indispensable to our food. An animal nourished entirely on food which is destitute of nitrogen would become weak and would soon die."
"Excuse me, Monsieur Roger," said Albert Dalize: "how can nitrogen enter into our food?"
"That is a very good question," added Miette, laughing; "surely you cannot eat nitrogen and you cannot eat gas."
"The question is indeed a very sensible one," answered Monsieur Roger; "but this is how nitrogen enters into our food. We are carnivorous, are we not? we eat meat and flesh of animals. ”

“ If the moon had been closer to the earth it would have fallen long ago; but it is more than two hundred and thirty-eight thousand miles away, and, as I have told you, if attraction or gravity acts upon the planets, it loses its power in proportion to the distance at which they are. The same attraction which forces the moon to turn around the earth obliges the earth and the planets to turn around the sun; and the sun itself is not immovable. It flies through space like all the other stars, bearing us in its train, subject also to universal attraction. ”

“ Monsieur and Madame Dalize looked up with astonishment. Miette gazed at Monsieur Roger without understanding.
"My dear friends," said Roger, turning to Monsieur and Madame Dalize, "you will not refuse me the pleasure of giving my fortune to Miss Miette. I have no one else in the world; and does not Mariette represent both of you? Where would my money be better placed?" ”

“ I need not therefore say oxygen is a colorless gas; and yet I will say it to you by force of habit. All books of chemistry begin in this way. Besides this, it is without smell and without taste. Oxygen is extremely well fitted for combustion. A half-extinguished candle—that is, one whose wick is still burning but without flame—will relight instantly if placed in a globe full of oxygen. Almost all the metals, except the precious metals, such as gold, silver, and platinum, burn, or oxydize more or less rapidly, when they are put in contact with oxygen ”

“ Why is it necessary to introduce air into the lungs?"
"Yes," said Miette; "let us pass to that."
"The blood, in going out of the heart, circulates to all the parts of the body in order to make necessary repairs; at the same time it charges itself with all the old matter which has been used up and is no longer any good and carries it along. Now, what is it going to do with this old matter? It will burn it. Where will it burn it? In the lungs. Now, there can be no combustion when there is no air. ”

“ So all bodies are subject to that force which we call weight; all substances, all matter abandoned to itself, falls to the earth."
Just here Miss Miette shifted uneasily on her chair, wishing to make an observation, but not daring.
"Come, Miss Miette," said Monsieur Roger, who saw this manoeuvre, "you have something to tell us. Your little tongue is itching to say something. Well, speak; we should all like to hear you."
"Monsieur Roger," said Miette, "is not smoke a substance?"
"Certainly; the word substance signifies something that exists. Smoke exists. Therefore it is a substance." ”

“ In this way Lavoisier discovered that the air was formed of a mixture of two gases: the first was oxygen, of which we have just spoken; the second was nitrogen. The nitrogen, which is also a colorless, odorless, and tasteless gas, possesses some qualities that are precisely contrary to those of oxygen. Oxygen is the agent of combustion. Nitrogen extinguishes bodies in combustion. Oxygen is a gas indispensable to our existence, with which our lungs breathe, and which revives our being. The nitrogen, on the contrary, contains no properties that are directly useful to the body. ”

“ It shoots in a straight line, ready to flee away from us; but suddenly the attraction of the earth makes itself felt. Then the moon bends downward to approach us, and the straight line which it had been ready to traverse is changed to the arc of a circle. Again the moon endeavors to depart in a straight line, but the attraction is felt again, and brings near to us our unfaithful satellite. ”

“ I must acknowledge to you that no one has yet seen the molecules of a body. Their size is so small that no microscope can ever be made keen enough to see them. A wise man has reached this conclusion: That if you were to look at a drop of water through a magnifying instrument which made it appear as large as the whole earth, the molecules which compose this drop of water would seem hardly bigger than bits of bird-shot. ”

“ There the substance in combustion, whether wood or coal, is a mass large enough to resist the violence of the current of air you throw in, and it profits from the air which you send to it so abundantly, by taking the oxygen which it contains and burning up still more briskly.
"Now, that is the answer to your last question; and I must beg you to remember your promise, and ask me no more hard questions to-night."
"Yes, friend Roger," said Miette, "I will leave you alone; you may go to sleep."
"And it will be a well-earned sleep," added Madame Dalize, with the assent of every one. ”

“ Weight, therefore, is the attraction of the earth for articles which are on its surface. Why does this table, around which we find ourselves, remain in the same place? Why does it not slide or fly away? Simply because it is retained by the attraction of the earth. ”

“ Animals placed in a globe full of nitrogen perish of asphyxia. In other words, they drown in the gas, or are smothered by it. I suppose you will ask me what is the use of this gas, and why it enters into the composition of the air? You will ask it with all the more curiosity when you know that the air contains four times as much nitrogen as oxygen; to be exact, a hundred cubic feet of air contains seventy-nine cubic feet of nitrogen and twenty-one cubic feet of oxygen. Now, the important part that nitrogen plays is to moderate the action of the oxygen in respiration. ”

“ Miss Miette wants to catch me," said Monsieur Roger.
Miette made a gesture of modest denial, but at heart she was very proud of the effect which she had produced, for every one looked at her with interest.
"To the smoke of which you speak," continued Monsieur Roger, "you might add balloons, and even clouds."
"Certainly, that is true," answered Miette, näively.
"Very well; although smoke and balloons rise in the air instead of falling, although clouds remain suspended above our heads, smoke and balloons and clouds are none the less bodies with weight. ”

“ In studying the fall of a body we find that in one second it traverses a space of sixteen feet and one inch. In falling for two seconds it traverses——"
"Twice the number of feet," said Miette, with a self-satisfied air.
"Why, no," said Paul; "because it falls faster during the second second, and in consequence travels a greater distance."
"Master Paul is right," replied Monsieur Roger. "It has been found that in falling for two seconds a body falls sixteen feet and one inch multiplied by twice two,—that is to say, sixty-four feet and four inches. ”

“ Monsieur Dalize got up, opened the door of the vestibule, and called Miette. She ran out gayly.
"What do you wish, papa?" she said.
"I want to see our friend Roger. Is he not in the parlor with you?"
"No; he always goes his own way. He does not talk to us any longer; and he has had a very funny, sad look for some time. He is not the same at all."
"Very well, my child," said Monsieur Dalize, interrupting the little girl. "Go back to the parlor and send me your brother."
Albert soon arrived. ”

“ For years, hardly losing any of its weight, a grain of musk spreads a strong odor. In a tubful of water one single drop of indigo communicates its color. The smallness of these particles of musk which strike the sense of smell and of these particles of indigo which color several quarts of water is beyond our imagination to conceive of. And these examples prove that bodies are nothing but a conglomeration of molecules. ”

“ The air composed of oxygen and nitrogen—for the nitrogen enters naturally with the oxygen—penetrates into the pulmonary cells, spreads itself through the blood, and is borne through the numberless little capillary vessels. It is in these little vessels that combustion takes place,—that is to say, that the oxygen unites with the carbon and that carbonic acid is formed. This carbonic acid circulates, dissolved in the blood, until it can escape out of it. It is in the lungs that it finds liberty. ”

“ If they are introduced into the body in too great a quantity, they do not find enough oxygen to burn them, and they are deposited in the adipose or fatty tissue, where they will be useless and often harmful. You see how indispensable oxygen is to human life, and you now understand that if respiration does not go on with regularity, if the oxygen of your room should become exhausted, if the lungs were filled with carbonic acid produced by the combustion of fuel outside the body, there would follow at first a great deal of difficulty in breathing, then fainting, torpor, and, finally, asphyxia. ”

“ Now, vegetables contain nitrogen. They have taken this nitrogen, either directly or indirectly, from the atmosphere and have fixed it in their tissues. Herbivorous animals, in eating vegetables, eat nitrogen, and we, who are carnivorous, we also eat nitrogen, since we eat the herbivorous animals. We also eat vegetable food, many kinds of which contain more or less nitrogen. Do you understand?"
"Yes, I understand," said Miette.
"There is nobody living who really understands this matter very well, for it is an extremely obscure, though very important, subject," replied Monsieur Roger. ”

“ A long and pointed tongue of fire extended itself from the flame of the candle. Monsieur Roger placed close to this tongue of fire the tapering and open end of the tube in which the water had finished boiling. The air, forced out of the blowpipe and thrust upon the flame of the candle, bore to this flame a considerable quantity of oxygen, which increased the combustion and produced a temperature high enough to soften and melt the open extremity of the tube, and so seal it hermetically. ”

“ We would find that cork weighs less than stone, that stone weighs less than lead, and that lead weighs less than gold. But, in order to compare these differences with each other, it has been necessary to adopt a standard of weight.
"I now return to Miss Miette's question,—'Why is lead heavier than cork?'—a question to which I had solemnly answered, 'Because its density is greater.' Miss Miette must now understand that cork, weighing four times less than water, cannot sink in water, although that process is very easy to lead, which weighs eleven times more than water. ”

“ However, as Miette obliges me, I shall speak. You see that all earthly bodies are subject to a force which has been called gravity, or weight. Now, gravity can also be called attraction. By the word attraction is meant, in fact, the force which makes all bodies come mutually together and adhere together, unless they are separated by some other force. This gravity or attraction which the terrestrial mass exerts upon the objects placed on its surface is felt above the soil to a height that cannot be measured. ”

“ Monsieur Roger took the shell off the egg and placed the egg thus deprived of its shell upon the empty carafe, somewhat after the manner of a stopper or cork.
"What I want to do," said he, "is to make this egg enter the carafe."
"Very well," said Miette; "all you have to do is to push from above: you will force the egg down."
"Oh, but nobody must touch it. It must not be a hand that forces it down, but by weight from above. No, the atmosphere must do this."
Monsieur Roger took off the egg, and lit a bit of paper, which he threw into the empty carafe. ”

“ Now, there is the important thing: because, in explaining to her what matter is, I will make her understand why lead is heavier than cork."
"Well, I am listening," said Miette.
And Master Paul respectfully added, in an undertone, "We are listening."
Monsieur Roger continued:
"The name of 'bodies' has been given to all objects which, in infinite variety, surround us and reveal themselves to us by the touch, taste, sight, and smell. All these bodies present distinct properties; but there are certain numbers of properties which are common to all. Those all occupy a certain space ”

“ He suddenly found a dark corner where everything disappeared; he could go no farther; but now that he knew Monsieur Roger's story, he was certain, absolutely certain that he had answered to the name of George in the fire at the farm. It was that name, that name only, which had suddenly shaken off his torpor and given him the strength to awake ”

“ The days passed by at the château of Sainte-Gemme quietly and happily. Monsieur Roger, having fulfilled his promise to give the explanation of gravity and of attraction, was careful to make no allusions to scientific matters. He thought it useful and right to let his little hearers find their own pleasures wherever they could. One afternoon he saw Miette and Paul leave the house together. Paul had two camp-stools, while Miette held her friend's album.
"Where are you going?" asked Monsieur Roger.
"We are going to sketch," answered Paul: "at the end of the park." ”

“ This venous blood becomes what is called arterial blood; this black blood becomes rich vermilion,—it is regenerated. It goes out again to carry life to all our organs. Now, this time," asked Monsieur Roger, pausing, "have I made myself understood?"
"Yes," said Miette, speaking both for Paul and for herself; "yes, we have understood,—except when you speak of oxygen, of carbon, and of combustion." ”