Galileo's Dream Read Free Page A

found in a box of odds and ends. While he did that, Galileo laid out their collection of lenses by type, fingering each, holding up two at a time and peering through them. Some he gave to Mazzoleni to attach to the ends of the tube.
    They only had the lamplit workshop to look at, and the area of the garden and arbor illuminated by the house windows, but it was enough to check for possibilities. Galileo looked at the lenses in the box, held them in the air. Inward, outward. The images blurred, went absent, grew diffuse, even made things smaller than what one saw with the eye alone. Although an effect the reverse of what one wanted was always suggestive.
    He wrote down their results on the open page of the workbook. Two particular convex lenses gave the image upside down. That cried out for a geometrical explanation, and he noted it with a question mark. The inverted image was enlarged, and sharp. He had to admit to himself that he did not understand light, or what it was doing between the lenses in the tube. He had only ventured to give classes on optics twice in seventeen years, and had been unhappy both times.
    Then he held up two lenses, and the potted citron at the edge of the garden appeared distinctly larger in the glass closest to his eye. Green leaf lit from the side by lantern light, big and sharp—
    â€œHey!” Galileo said. “Try this pair. Concave near the eye, convex at the far end of the tube.”
    Mazzoleni slotted the lenses into the frames and gave the tube to Galileo, who took it and pointed it at the first tree branch in the arbor, illuminated by the lit windows of the house. Only a small part of the branch appeared in the tube, but it was definitely enlarged: the leaves big and distinct, the bark minutely corrugated. The image was slightly blurred at the bottom, and he shifted the outside frame to tilt the glass, then rotated it, then moved it farther out on the tube. The image became sharper still.
    â€œBy God it works! This is strange!”
    He waved at the old man. “Go to the house and stand in the doorway, in the lamplight.” He himself walked through the garden out into the arbor. He trained the tube on Mazzoleni in the doorway. “Mother of God.” There in the middle of the glass swam the old man’s wrinkled face, half-bright and half-shadowed, as close as if Galileo could touchhim, and they were fifty feet apart or more. The image burned into Galileo’s mind—the artisan’s familiar gap-toothed grin shimmery and flat, but big and clear—the very emblem of their many happy days in the workshop, trying new things.
    â€œMy God!” he shouted, deeply surprised. “It works!”
    Mazzoleni hurried out to give it a try. He rotated the frames, looked through it backwards, tipped the frames, moved them back and forth on the tube. “There are blurry patches,” he noted.
    â€œWe need better lenses.”
    â€œYou could order a batch from Murano.”
    â€œFrom Florence. The best optical glass is Florentine. Murano glass is for colored trinkets.”
    â€œIf you say so. I have friends who would contest that.”
    â€œFriends from Murano?”
    â€œYes.”
    Galileo’s real laugh was a low
huh huh huh
. “We’ll grind our own lenses if we have to. We can buy blanks from Florence. I wonder what would happen if we had a longer tube.”
    â€œThis one is about as long as we’ve got. I guess we could make some longer sheets of lead and roll them up, but we would have to make the molds.”
    â€œAny kind of tube will do.” Here Galileo was as good as Mazzoleni or any artisan—good at seeing what mattered, quick to imagine different ways of getting it. “It doesn’t have to be lead. We could try a tube of cloth or leather, reinforced to keep it straight. Glue a long tube of leather to slats. Or just use cardboard.”
    Mazzoleni frowned, hefting a lens in his hand. It was about the same