"Y OU told us," said Claire, "that at the same time the earth turns on its axis it travels round the sun."
"Yes. It takes three hundred and
"The earth takes one day of
"That is it. Imagine yourself turning around a circular
table the center of which is occupied by a lamp representing
the sun, while you represent the earth. Each of your walks
around the table is one year. To represent things exactly,
you must turn on your heels three hundred and
"It is as if the earth waltzed around the sun," Emile suggested.
"The comparison is not so well chosen as it might be, but it is exact. It shows that in spite of the giddiness of his age Emile has understood perfectly. A year is divided into twelve months which are: January, February, March, April, May, June, July, August, September, October, November, December. The unequal length of the months is sometimes confusing. Some have 31 days, others 30; February has 28 or 29, according to the year."
"For my part," said Claire, "I should find it hard to tell whether May, September, and other months have 30 or 31 days. How can one remember which months have 31 days and which 30?"
"A natural calendar, engraved on our hands, teaches us in a very simple way. Close the fist of the left hand. At the knuckles the four fingers, other than the thumb, form each a bump, separated by a hollow from the next bump. Place the index finger of the right hand in turn on these bumps and hollows, beginning with the little finger, and at the same time name the months of the year in order: January, February, March, etc. When the series of the four fingers is exhausted, return to the starting-point and continue naming the twelve months on the bumps and hollows. Well, all the months corresponding to the bumps have 31 days; all those corresponding to the hollows, 30. You must except February, answering to the first hollow. That has 28 or 29 days, according to the year."
"Let me try," proposed Claire. "We'll see how many days May has: January, bump; February, hollow; March, bump; April, hollow; May, bump. May has 31 days."
"It is as easy as that," said her uncle.
"My turn now," interposed Jules. "Let us try September: January, bump; February, hollow; March, bump; April, hollow; May, bump; June, hollow; July, bump. And now? I am at the end of my hand."
"Now begin again and go on naming the months," Uncle Paul instructed him.
"You go on at the same point where you began?"
"All right. August, bump. There are two bumps in succession. There are then two months together, July and August, that have 31 days?"
"I will begin again. August, bump; September, hollow. September has 30 days."
"Why has February sometimes 28 and sometimes 29 days?" asked Claire.
"I must tell you that the earth does not take exactly 365 days to turn around the sun. It takes nearly six hours more. To make up these six hours that were disregarded at first in order to have a round number of days in the year, they are reckoned in every four years, and the additional day they make all together is added to February, which then becomes 29 days long instead of 28."
"So, for three years running, February has 28 days, and the fourth year it has 29."
"Exactly. Remember, too, that the years when February has 29 days are called leap years."
"And the seasons?" queried Jules.
"For reasons that would be a little too difficult for you to understand yet, the annual journey of the earth around the sun causes the seasons and the unequal length of days and nights.
"There are four seasons, of three months each: spring, summer, autumn, and winter. Spring is from about March 20th to June 21st; summer from June 21st to September 22d; autumn from September 22d to December 21st; winter from December 21st to March 20th.
"On March 20th and September 22d the sun is visible 12 hours and invisible 12 hours, from one end of the earth to the other. The 21st of June is for us the time of the longest days and shortest nights; the sun is visible sixteen hours and invisible eight hours. Farther north the length of the day increases and that of the night diminishes. There are countries where the sun, an earlier riser than here, rises at two o'clock in the morning and sets at ten o'clock at night; still others where the time of its rising and that of its setting are so close together that the sun has hardly sunk below the apparent edge of the sky before it appears again. Finally, at the very pole of the earth, that is to say at the point that remains stationary, like the end of the axle of a wheel, while all the rest turns, one could witness the wonderful spectacle of a sun that does not set, that turns around the spectator for six whole months, equally visible at midnight and midday. In those countries there is no longer any night.
"On the 21st of December we have a state of affairs just the reverse of that observed in June. With us the sun rises at 8 o'clock in the morning; at four in the afternoon it has already set. That is eight hours of day for sixteen of night. Farther north there are now nights of 18, 20, 22 hours, and corresponding days of six, four, and two hours. In the neighborhood of the pole, the sun does not even show itself, and there is no longer any daylight; for six months there is the same darkness in the middle of the day as at midnight."
"And do people live in that country of the pole, where the year is composed of a day lasting six months and a night of six months?" asked Jules.
"No, up to this time
man has not been able to reach the pole on account of the
horrible cold there; but there are countries more or less
near the pole which are inhabited. When winter comes, wine,
beer, and other beverages turn into blocks of ice in their
casks; a glass of water thrown into the air falls back in
flakes of snow; the moisture of the breath becomes needles
of rime at the opening of the nostrils; the sea itself
freezes to a great depth and thus increases the apparent
extent of the dry land, which it resembles, having, like it,
its fields of snow and mountains of ice. For whole months
the sun does not show itself, and there is no difference
between day and night, or rather it is one long night, the
same at midday as at midnight. However, when the weather is
fine darkness is not complete; the light of the moon and
stars, augmented by the whiteness of the snow, produces a
kind of semi-daylight sufficient for seeing. By this wan
light, in sledges drawn in disorderly fashion by teams of
dogs, the people of these dark regions hunt what scanty game
there is. Fishing furnishes them more abundant food.
dried, stored, half decayed, and rancid whale's blubber are
their habitual food. For fuel for their hearths their
dependence is, again, on their fishing which supplies them
A Part of the Moon's Surface
"Oh, the doleful countries!" cried Emile. "One more question, Uncle. In traveling around the sun does the earth go fast?"
"It takes a year for the entire tour; but as it circles at an enormous distance from the sun, a distance of 38 millions of leagues, it must travel this wide circle with a speed beyond your power to conceive. This speed is 27,000 leagues an hour. In the same time the fastest locomotive goes about 15 leagues. Compare and judge."
"What!" exclaimed Jules, "the immense ball of which we have never been able to comprehend the frightful weight travels in the sky with such rapidity?"
"Yes, my friend; with a speed of