Horowitz was happy there. He enjoyed the long hours of mindless work, and still does today. "Science is far more tedious than people realize," he says. "But I have a high boredom threshold, and a low thrill threshold. Looking through a telescope might sound exciting, but you're not watching galaxies explode. There are very exciting times, but those times are few and far between. You have to be happy in between."

Horowitz has always found much of his amusement in dreaming up gadgets, off-beat electronic gear that no one has built before, whether by choice or by oversight. As offshoots of early hobbies, he built a teletype for ham operators that transmits in Morse Code, and a metronome that, with a few adjustments, clicks out a syncopated beat. Lately, he seems most tickled by a small box he and two undergraduates built, which has been programmed with the algorithms of various types of music. Given a note, the machine will make a random choice based on probabilities of which note to hit next, and how long to hold it. The result is an inoffensive if bland series of electronic tones, reminiscent of belly-dancing one moment and, after flicking a few switches, baroque music the next. It's not great music, but it's music nevertheless. The box took two hours to design.

* * * * *

Horowitz arrived at the morning appointment that had become a lunch date 30 minutes late, but took the time to lock his new calculator--an $800 model from Hewlett-Packard that can run a computer program--deep in his trunk, pushing aside neatly arranged tools and a box of his own microphones, still in his car since Yo Yo Ma's last concert. Horowitz tapes many of the cellist's concerts, using equipment he designed and built himself, as he has become good friends with Ma. In college Horowitz played a little cello himself--he was better at building metronomes--and was an early fan of Ma's. When he was looking for music for his wedding, he called up Ma, even though they had never met. Charmed by the directness of the request, Ma agreed to play. Horowitz has taped several of his concerts since, and the physicist and the music major often talk by phone, discussing performances and laughing at gadgets that would make music.

Horowitz replaced the microphones, carefully closed the trunk, and walked into the offices of the little firm, a manufacturer of pinholes no wider than a wavelength of light, and found that now he had to wait. The owner of the firm was on the telephone, but Horowitz didn't mind. He glanced through some brochures on laser equipment, and then stared into the rain, wondering how long it would take his dog, a Siberian husky, to dry when he returned home that evening and let him in.

Horowitz had called the owner of the company the week before in search of a pinhole for his proton microscope, but quickly found that he knew better ways of making distortion-free pinholes than anyone else. He spent months developing his own technique when he was a graduate student working on an X-ray microscope, and though he published his method he never bothered to patent it. Now the owner wanted to learn how to make them, and hoped to hire Horowitz as a consultant.

Lunch was at a nearby sandwich house. Horowitz looked at the menu and said, "It looks like we're supposed to order The Special." The Special, a steak on bread with beer, would take a few minutes more than the sandwich his prospective partner ordered, so while the pinhole manufacturer nibbled at his food as slowly as possible, he and Horowitz made mannish talk about beers. Both gushed over the legendary Coors, bemoaning its scarcity east of the Rockies. Horowitz talked about the virtues of American draught, mentioning a few brands. The manufacturer hadn't heard of them.

The manufacturer's real gaps in knowledge became apparent when, while mopping up his plate, Horowitz changed the subject to science. He described his techniques, and patiently answered questions that were not always good. The questions would continue back at the offices, where