While researching his new book on Apple Computer Inc., author Michael Moritz found the company's co-founder, Steven Jobs, to be the strong, silent type -- too silent, in fact. About halfway through the project, a definitive hush fell over Jobs, who turns 30 years old this month.

The temperamental Apple chairman spent few words explaining himself. "At some point, the spigot was just turned off," says Moritz, author of The Little Kingdom: The Private Story of Apple Computer. "People were told not to speak to me. Jobs decided not to talk to me anymore. I told him I intended to continue to write, and we left it at that."

Moritz, who was formerly the San Francisco bureau chief for Time magazine, says that Jobs was upset over the direction the book was taking. What Jobs wanted, says Moritz, was a book about the birth of Macintosh, Apple's hot new computer. His model was Tracy Kidder's The Soul of a New Machine, a Pulitzer prize-winning account of the creation of a Data General Corp. computer. Moritz wanted to write a corporate profile instead.

Jobs was also incensed by a profile of him that Moritz reported for Time two years ago. Sources described Jobs as insensitive, arrogant, and brash -- but also gave him credit as the "prime advance man for the computer revolution." Jobs wasn't humored. "After that," Moritz says, "he didn't feel he could be sure of me."

And he couldn't, as it turned out. In The Little Kingdom, Moritz shatters the myth of Apple as a relaxed, humanistic company. In reality, says Moritz, Apple continually "burns out engineers and replenishes them with fresh young ones," as in the case of company co-founder Stephen Wozniak. And Jobs has become so intense during some corporate powwows that he has broken into tears. When asked to comment on the book, Jobs continued his definitive hush.