Let us look at the subject from a distance, that we may understand it
more clearly. Let us imagine a horse drawing a heavy cart slowly along.
Ask it to gallop, and it will answer, "With all my heart! but you must
give me a lighter carriage to draw." And now fancy another flying over
the ground with a gig behind it. Ask it to exchange the gig for the
cart, and it will say, "Yes; but then I shall have to go slowly."

Whereby you see that with the same amount of strength to work with,
one has the choice of two things: either of conquering a great
resistance slowly, or a slight one quickly.

And it is partly on this account, dear child, that I teach you so
gradually; for young heads, fresh to the work, are less easily drawn
along than others, and have but a certain amount of strength.

Hitherto all has been clear as the day. Now take your scissors in your
left hand; hold the lower ring of the handle firmly between your thumb
and closed hand, so that the blade shall remain straight and immovable:
then with your other hand cause the upper ring to go up and down, and
watch the blade as it moves. The whole of it moves at once, and is put
in motion by the same power--viz., your right hand. But the point makes
a long circuit in the air, while the hinge end makes only a very little
one--indeed, moves almost imperceptibly: and, as you may imagine, a
different sort of effort is required from the motive power (your hand)
according as resistance is made at the point or at the hinge. The point
goes full gallop: it is the horse in the gig; the light work is for
him. The hinge moves slowly; it is the cart-horse, and takes the heavy
labor.

I hope I have made you understand this, for it explains the cracking