Labor Day weekend in 1969—Saturday, Aug. 30, to be more precise—deserves more prominence in history books. At any rate, that is what Andrew Blum, a correspondent for Wired magazine, wants us to believe: He says the date marks the "Internet's physical birth." It was then that the Interface Message Processor No. 1—the first of the many machines that would eventually be linked into the Defense Department's network known as the Arpanet—arrived on the campus of the University of California in Los Angeles. By Oct.