This project uses information from digitized Google books and library catalogues to create new measures of technological innovation and diffusion for OECD countries from 1850 to the present. Once completed, the new series will be used, first, to map the waves of innovation over time and space, second, to estimate the economic impact of the technologies, third, to plot technological diffusion both within and across countries, and, fourth, to re-examine the nature and economic consequences of general purpose technologies. The results will further our understanding of business cycles and the contribution of technical change to growth and to international productivity and income differentials.