Billy stared out the shed window at the pouring rain. “Nothing to do,” he muttered.
“That’s funny,” said Grandfather. “The world is so full of interesting things for me that I hardly know what to do first.”
“What are you making, Grandfather?”
“I’m making a music box for a little boy I know.”
“Who, Grandfather?” asked Billy, enjoying this game that they often played. “Do I know him?”
“I’ll give you three guesses.”
“Is he a bad boy?”
“No. I never give presents to bad boys,” Grandfather replied, his eyes twinkling.
“I know. It’s for me!”
“Right. But only if you help me make it. See all these rubber bands? There are wide ones and narrow ones, thick ones and thin ones. Some of them will be the strings for your music box.
“We’ll use this sturdy cardboard box that has a lid. I’d guess it’s about seven inches long, maybe four inches wide, and two inches deep. Take this pencil and ruler, Billy, and draw a one-and-a-half-inch line sideways on the center of the lid just above its middle [see illustration]. Now take this knife and carefully cut through the lid on the line you’ve drawn.”
Billy cut a neat slit.
“Good,” said Grandfather. “Now I’ll draw a half-moon an inch above the slit [see illustration]. Can you cut along that?”
“I’ll try, Grandfather.”
“Not so hard, was it? I’ve made a two-inch bridge out of stiff cardboard. It has a little tab on the bottom of it. The tab is an inch and a half long and must fit snugly into the slit you just cut. See if that tab fits into the slit.”
“Is that OK, Grandfather?”
“Fine and dandy. Put the cover on the box, and we’ll put a line of glue around the bridge where it touches the lid to make the bridge secure.”
After the glue had dried, Grandfather said, “Now, Billy, put this narrow rubber band around the box and over the bridge.”
Billy struggled a bit, but finally he had the rubber band on the box straight.
“Now it’s my turn,” said Grandfather, smiling. He added a slightly wider rubber band. Soon they had five of them on the box.
“Let’s see how it sounds,” said Grandfather. He plucked the strings. “Ouch! That one is sour. Let’s try another one.”
“That sounds good,” Grandfather said, pleased. “Now let’s arrange the rubber bands by pitch, starting with the highest tone.”
It took several minutes to change the bands. Then Billy plucked them. “It really makes music, Grandfather! Thank you.”
“We can improve its sound by putting a tighter band here,” Grandfather suggested, plucking a loose one. Plunk!
After adjusting and changing two bands, Billy learned that by pushing a a rubber band down with his finger and then plucking it, it would sound higher than it did before. The closer to the bridge he pushed on a rubber band, the higher the note he could play. Soon he was playing “Three Blind Mice,” “Popcorn Popping,” and lots of other favorite songs. “Grandfather,” he said happily, “I hope you’re always here when I have nothing to do.”