The Teacher and Pupil.
We now return to Walter Wallace, who we left on the banks of the
Callicoon in company with Surveyor Webb and party. Webb soon discovered
that Walter was a boy of more than ordinary intelligence, and that his
education had not been neglected. He could read and write, and had made
some advancement in arithmetic.
They returned to camp about noon and eat a hearty dinner to which Walter
did ample justice, although he had eaten a late breakfast.
Webb had been pondering in his mind upon the propriety of asking Walter
to become one of his party, and retain him, if possible, until the survey
of the Minisink country was completed. To that end he said to Walter:
Are you willing to remain with me and learn to survey?
I am willing to do anything I can, the boy replied, but I have not got
learning enough to read the figures on that thing.
But you can learn, said Webb.
I can try, replied Walter.
That is all that is required. You must try and be accurate. There is no
such thing as good enough. Everything must be done accurate.
I will try my best, said Walter.
That is all that is required, and to-night I will give you the first
lesson.
After supper, Webb and Walter went to the top of the hill. The compass
was properly adjusted on the tri-pod.
Now, said Webb, I want you to level the instrument. That is very
important. Unless the compass is exactly level, the needle will not
balance.
Walter took hold of one of the sights and attempted to level the
instrument, but failed.
Take hold of both of the sights, boy, one with your right and the other
with your left hand. Use force enough to bring the bubbles in the centre
of the glasses forward. Then do the same with the cross level.
I see, said Walter. This glass levels it one way and the other glass the
other way, and when the bubbles are in the centre of both glasses, the
compass is level. Let me try it again.
He did so, and the compass was level.
Bravo! exclaimed Webb. You have mastered one of the most difficult parts
of the adjustment of the compass. Now take hold of that screw on the
under side with your thumb and finger, and turn it around until the
needle moves.
He did so, but excitedly stepped back as if he had seen some apparition.
Don’t be frightened, boy, it will not hurt you.
It is alive! It moves! exclaimed Walter excitedly.
You are half right boy. It moves but there is no life there.
What makes it move? See! It goes first one way and then the other.
True, but it will soon stop, said Webb.
But what makes it move? Black iron can’t move itself. Is there wheels in
there that moves it like father’s clock?
No. It moves by the same force that exists in nature, which is but little
understood. We know the fact that it does move, and that is about all we
know about it.
But it is boxed up tight. The hand can’t touch it, or the wind blow it.
But something makes it go. What makes it go?
That is a mystery I cannot fully explain myself, but as you progress,
you will learn as much about it as I know myself, and I trust much more.
There are a great many things in nature that are beyond the comprehension
of man, that time and study will generally explain.
But it has stopped. It is now perfectly still. What stopped it? Father
used to say that if a body was put in motion, it would never stop unless
it came in contact with some other body. But nothing has come in contact
with it.
You are slightly mistaken in that. There is a slight friction on the
centre pin. Yet that did not stop the needle. The fact is, the same
invisible power that started it, stopped it. But I will explain more
about it when you have learned its uses. You will see that on one end is
a small copper wire wound around it. That is to balance the needle on the
centre pin, and denotes that it is the south end of the needle. The other
end always points to the north.
How can you know that? asked the boy.
Because it always points directly, or nearly directly towards the north
star. If the needle gets out of order it will not point to the star. Now
turn the compass so that the needle will be directly back of the letter N.
Walter did so.
I can’t see any star there. Now I see hundreds of them. Which one is the
north star?
It is a small, twinkling star. It will appear and then disappear. Did
your father ever show you the big dipper, or great bear?
Oh, I know the big dipper, but I never saw the great bear.
They are both one, boy. The two lower stars are called pointers. Look to
where they point to, and tell me what you see?
I see the small, twinkling star you spoke of. I will never forget that.
I suppose that the pointers on the dipper always point the same way, and
that I can find the star by looking at the pointers?
You are partly right. You can always find the star by following up the
pointers, but the dipper changes. It is now south-west of the star. In
two months it will be directly under it. Thus it continues to revolve
around the star, but the pointers always point towards the star.
To adjust the compass and take the sights are simple and easy, and I
think you will learn to do it in a few days as well as I can. But you
have got to study the books and learn how to calculate the area and
angles. Now we will return to camp, and in the morning you can set the
compass on a line North, forty-five degrees West.
Walter retired, but slept but little that night. He was highly elated at
the prospect of learning to survey, had many misgivings as to whether he
would succeed. But if study and perseverance had any virtue, he was bound
to succeed.
As soon as it was light in the morning he was up and out with his
compass. It was some time before he could adjust the compass to his
satisfaction, but at last he accomplished it. He next liberated the
needle, by means of the thumb screw.
The moment the needle began to move, he became excited. The idea of a
dead piece of iron moving itself was something above his comprehension.
He thought it must be moved by some supernatural power. Why, he thought
to himself, did not Mr. Webb tell me where the force comes from? He
talked as if neither himself or anybody else knew the cause! He next set
the compass as he thought North, 45° West, but the sights pointed East of
North, and he was pondering over this, when Webb arrived.
Good morning, Walter, I see that you are up and at it early. You have the
compass very correctly adjusted. What course do you say it points? I told
you North, 45° West. Is that it?
That is what the figures say, yet it points to the Northeast instead of
Northwest.
You have fallen into a very common error. Now look and you will see
that the letters E and N are reversed on the compass consequently when
you wish to run N. W., the North end of the needle must be between the
letters N. and W., and to run N. E., between E. and N. Now set the
compass on the figures 45, between N. and W., and you will have the
course we are running.
As if by instinct, the boy set the compass on the course indicated.
Well done, said Webb. Now let us get our breakfast, and then you can take
charge of the compass.
Breakfast was eaten, and the whole party went to the place where they
quit work the day before. By the direction of Webb, Walter set the
compass over the centre stake, with the needle pointing N., 45° West.
Well done, boy! Now you see sights on both ends of the compass, with
large holes. Between them are fine slots. Now you must look through both
of these sights at the flag ahead, and when you can bring the two sights
and the flag in range, you are right.
Walter motioned the flag to the point he thought in range, and said:
There! I guess that is right!
You must not guess; you must know, replied Webb. Let me look. You have
made another common error. You have sighted through the large holes. Try
again and look through the slots.
Walter looked again and saw that the flag was twenty feet out of line.
Go South! he cried. Now, Mr. Webb, I _know_ that I am right.