Elisabeth was out in the back field when Adam arrived home. She was absorbed
with a drawing she was making of the setting around the pond. In the preceding
year she had taken an interest in pencil sketching and was proving to have a
talent for it. Adam noiselessly walked up behind her and looked over her shoulder
at the sketch. After silently watching her work for a while he commented, "That
oak tree isn't nearly so big. You're making it at least twice the size."
Elisabeth looked up with a start. "Adam... you're back."
"Just got back. I haven't started to unload the car yet. I hear you're turning
into quite the artist."
"I'm getting better. I know the tree isn't that big, but they take so long to
grow. I can't wait around for it. You say that's an oak tree?"
"Yes. A red oak. Its technical name is 'Quercus rubra'."
"Quercus rubra," she repeated. "Did you learn that at university?"
"Mm-hm. I learned other things about it too: what the wood looks like under a
microscope, how water is pulled from the roots up the stem, how the leaves use
sunlight to make food...."
Elisabeth gathered her drawing utensils together and the two of them headed
back to the house.
"And what else did you learn at university?" she asked.
"Oh, lots of other things. I couldn't begin to tell you them all just now. But
by and by I'll tell you more."
Adam's first opportunity to explain to her something more of his learning came
a few days later. There had just been a shower of rain and across the sky to the
east arched a brilliant rainbow. He and Elisabeth were outside admiring the
spectacle. She wished that she knew how to paint because a pencil sketch could do
nothing with the colors. Adam saw the whole phenomenon as the interplay of various
laws of physics.
"You see, Elisabeth," he explained, "a rainbow is the result of reflections and
refractions - that means bending - of sunlight from the millions of individual
raindrops in a passing shower. Raindrops aren't teardrop-shaped as you might
think. Actually they're almost perfect spheres. Now, consider the geometry of the
situation. The rays of sunlight striking each raindrop are almost perfectly
parallel. They enter the drop, are refracted - bent - slightly, then bounce off
the inside far wall of the drop and exit out the front surface again at an angle
of about forty-two degrees relative to the ray of incoming light. Each single
ray of sunlight is composed of several different colors, each color having a
different wavelength. Each wavelength is bent slightly differently as it passes
through the raindrop, and the colors are spread out and separated as they reflect
back toward the sun. An arch of several colored bands results.
"You can see two bows actually, if you look carefully. There's a bright,
primary bow on the inside of the arch and a fainter, secondary bow above it. The
formation of these two bows is a result of the index of refraction of the surface
of the raindrop, where the air and water meet - about one and three tenths. The
refraction index refers to the degree of bending; it varies with different
substances. If we could replace the raindrops with a different material having a
higher index of refraction, we could alter the composition of the rainbow. For
instance, in a shower of pure, spherical diamonds with a refraction index of two
and a half, the primary bow would disappear and there would be no rainbow at all.
Do you follow me, Elisabeth?... Elisabeth?..."
Adam had been looking at the rainbow throughout his dissertation and turned to
see where his sister had gone. She was only a few feet behind him, trying to
remove a clump of burdock burs from the dog's coat.
"Were you listening to anything I said?" he asked with a tone of annoyance.
"Some of it," she replied with such genuine disinterest that she was rather
Adam sighed and helped her cut out the burs with a pocketknife.
Over the course of the summer, a change became apparent in the way that Adam
looked at common sights around him. At night when a sphinx moth flew up to the
light bulb on the back verandah, the insect did not merely approach the bulb -
rather, it approached it along a logarithmic spiral. The cattle no longer just
had various patterns of black and white patches on their coats - rather, they
had underlying genotypes that accounted for these surface phenotypes. When
Adam constructed a stook of sheaves in the field, he was no longer just helping
with harvest - rather, by arranging the randomly scattered sheaves into the
orderly structure of a stook, he was decreasing the entropy of the field's grain.
Adam could analyse a sunset into wavelengths and frequencies, and the fragrance
of a rose into component chemicals. His mind was always taking apart, breaking
down, and endeavoring to reduce to simpler terms anything it encountered.