ial revolution number 3, he writes created only a short-lived growth revival between 1996 and 2004. Many of the original and spin-off inventions of IR #2 could happen only once - urbanization, transportation speed, the freedom of females from the drudgery of carrying tons of water per year, and the ro

ber two, which saw "80 years of relatively rapid productivity growth between 1890 and 1972." According to Gordon, once "the spin-off inventions from IR #2 (airplanes, air conditioning, interstate highways) had run their course, productivity growth during 1972-96 was much slower than before." Industrial