Popular Science Monthly/Volume 20/January 1882/Astronomy in High-Schools

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ASTRONOMY IN HIGH-SCHOOLS.

By MISS ELIZA A. BOWEN.

I HAVE for some years been much interested in trying to introduce improved scientific teaching into girls' schools; and I propose to tell the result of some experiences in teaching astronomy.

Of course, the astronomy taught has been of the most elementary character. But it is therefore exactly the foundation which it is important to lay well. My object has been to gain for my pupils from this study, not merely knowledge, but all the mental discipline it could afford. In order to accomplish this, I have made it an invariable principle to make them do all the observing, all the thinking, possible. They have watched the heavenly bodies to discover their appearance and motions, and then I led them on to discuss the causes. It has been genuine inductive study, so far as it has gone. My own work seemed very simple; but it occasioned me a great deal of observation, thought, and study. I have simply kept them on the track.

It may at first seem a little absurd to talk of a set of school-girls treading, with any degree of mental independence, the path which Kepler and Tycho Brahe found it so difficult to walk in. Of course, it would be utter nonsense to say that they could exercise anything like the mental activity of those great men. But there are various degrees of the mind's activity, and it is possible to arouse, even in school-girls, a very wholesome and improving. amount of it.

When I first began, I merely intended to make some girls of seventeen years old, who were soon to study Lockyer's "Astronomy," do some preparatory observing. I soon saw that it would have been desirable to begin earlier: and, in the room in which I talked to these young ladies, there were seated at desks some young girls of Thirteen and fourteen years old, who listened to my talk and directions with great interest, and, as I soon found, were observing and thinking with as much energy as their older companions. It became out of the question to refuse instruction to those who showed themselves so capable of learning. All the work of which I am about to tell was well performed by girls of fourteen years old.

The method I tried can best be understood by one or two illustrations. I will first say, briefly, thai they found for themselves the chief stars in nearly every important constellation by drawings I made on the blackboard or on bits of paper (aided by my hectograph). As soon as they learned the Dippers in Ursa Major and Ursa Minor, and Cassiopeia, I put them to making observations at an interval of several hours on the same night, so as to find out the daily apparent motion. Thus far they knew Polaris only as "the star in the handle of the Little Dipper." It was some days before all reported observation, and I did not indorse any report until we had full concurrent testimony that from 6 p. m. to 12 the Great Dipper moved down toward the horizon and then east (it was autumn), that Cassiopeia moved up and then west, and that the bowl of the Little Dipper had turned on the handle until it was nearly upside down. They drew the Little Dipper on the blackboard, and made arrows to indicate the direction in which the other constellations moved. They remarked, without prompting, that the arrows made a kind of circle. After another night's observation, the report was brought that at 6 p. m. the constellations had returned to the positions occupied by them at 6 p. m. of the previous day. They said the stars must have gone entirely round that star in the handle of the Dipper, or else have moved backward. By this time the interest had become so great that a number of girls rose before day to take a look; so we had a further report. When they had settled as fully as they could the fact of the apparent motion, I asked them, "When an object seems to move, does it always prove to be in motion? "Many cited in answer the apparent motion of the trees when one journeys by rail. After drawing from them the fact that the real and the apparent motions are always in opposite directions, I asked, "Do you think the earth is turning round, or are the stars moving round it? "Up to this time several intelligent girls had been without suspicion that they were coming round to the familiar fact of the earth's rotation on its axis, learned from the beginning of their geographies. Their surprise, when my question flashed this result on them, was very amusing. It was to me a striking illustration of the inadequacy of learning things about nature from books alone.

I will not weary the reader with an account of the observations which detected the apparent annual motion of the stars, and the facts and questions which led them to conclude that it resulted from a real motion of the earth, in a circle, with the sun in the center. They also detected the apparent motion of the sun north and south, and had a very interesting discussion whether this was real or apparent. In the course of this study, they experimented in a darkened room with a light, and a ball revolving on its axis. The ball was held at the solstitial and equinoctial positions, and revolved, and they drew the conclusions regarding length of days. The work was just as much as possible their own.

One of the most interesting studies made by my pupils was that of the moon. They began with the new moon, and of course very soon accounted for its daily apparent motion west, Then they watched the real motion from night to night. I must not forget to say that regular books were kept by them for recording observations. They kept account of the phases and the corresponding relative positions of the sun, moon, and earth. This led to a very interesting discussion as to what makes the moon shine. In the course of this, they drew diagrams and experimented with the ball and light. They detected the earth-shine, and settled its cause for themselves; found out that the moon moves round the earth, and noted the time; noted the hours of rising; noted the various constellations through which the moon takes its path; and noted the effect of their situation on the moon's time of rising. After these points had been settled, I asked them, had they ever seen the moon show more than one face. As this called attention to the fact that the moon always shows (substantially) the same face, the cause was discussed. To settle it, a girl stood in the middle of the room and another walked round, facing her all the time. They finally settled for themselves that the moon revolves once on its axis while it moves once round the earth. I gave them no further help than the question I have just stated. I have not yet had pupils trace the moon's path and that of the sun so accurately as to discover the nodes, but I certainly shall try to do so, and to have the retrograde motion of the nodes detected; the time (approximate) of their revolution. I shall pass over nothing that ordinary eyes can see, ordinary minds reason out.

The study of planets affords delightful work. Some of my pupils have studied Mercury with great interest, finding that his orbit is within that of the earth and of Venus; finding the direction of his motion round the sun, and the period. The study of Mars is in the highest degree profitable, and so is that of Venus. The young folks can readily discover the retrograde motions, and, with the simple suggestion that the apparent retrograde may result from the changed position from which we view the planet, may find the relative positions and detect the cause.

I occasionally report to my young astronomers a little of the testimony of other persons. Thus, in discussing the cause of the moon's light, I told them of stars occulted by the dark part of the moon. In doing so, I always wait until they have exhausted the evidence of their own senses; and I am specially careful to distinguish between the two kinds of testimony. It leads, with older girls, into some very interesting discussions as to the value of other people's evidence.

Sometimes some of the girls begin to guess. I always take special care (in a good-natured way) that guessers shall come to shame. I endeavor to make them as accurate as possible, allowing the evidence to prove just what it ought, and no more.

My pupils have been so much interested in astronomy, that their talk about it has brought to me a good many persons who wish to sell me some sort of apparatus for illustrating the motions of the solar system or some part of it. I do not much believe in these contrivances. They are very apt to take the place of the observation of nature, a very pernicious result. Besides, to understand the motions, one must study each separately. The observation of nature must precede the illustration of nature. A light and a ball revolving on its axis sometimes help. The very simplest apparatus is the best. Young folks have a superstition about complicated apparatus. It begets a vague wonderment which is very far removed from a scientific temper. God's own great machinery is undoubtedly the thing to study. But a small telescope would enlarge greatly the field of observation. The pupils could, with its aid, study Jupiter's miniature system, the rings of Saturn, the phases of Venus and Mercury; and, by the sunspots, they could detect the revolution of the sun on his axis. Mr. Whitall, of Phillipsburg, New Jersey, gets up a small telescope for fifty dollars which would be of great use. I find the astronomers who wish to do original work have great contempt for a telescope costing less than eight hundred dollars. Mr. Whitall's telescope is probably better than that which discovered Jupiter's moons and Saturn's rings, and, for the sort of teaching I have described, would do a great deal of good.

I have a good deal of trouble with people who are attracted by the interest of my girls, and who always want to tell them the things they ought to find out for themselves. Bright young fellows from college, who want to show off before the girls, are particularly given to this. But my pupils themselves aid me, for they do not wish to be told.

It is important to have a good deal of drawing. Fortunately, in the best schools, the importance of this art is now appreciated. The constellations should be drawn from nature and from memory, with a statement on each map of the boundaries. When any planet is under study, I always have diagrams drawn showing its various positions in relation to the sun and the earth.

I do not pretend that this is other than the most elementary work, and I do not myself pretend to be much of an astronomer.

There is nothing wonderful in teaching as I have described, but it is certainly a great mistake to teach otherwise. It is probable that, in the active centers of thought, others have adopted this plan. It is certainly far from general. I am sure nearly all teachers of girls would find their own knowledge made more accurate by the observation and study it requires. Teachers in boarding-schools, who are with their pupils at night, could accomplish admirable results; and I should think intelligent parents would be delighted to train their own children.