In this volume in the NBER series on capital formation and financing, the authors show, with supporting figures, two major trends in mining and manufacturing. The first is that this sector had a rate of growth significantly higher than that of the economy as a whole. The total capital assets of this sector increased fifteenfold from 1880 to 1948, while the total stock of all tangible wealth in the United States increased only about sixfold. The second trend is a marked diversity among industries in the rate of growth over the period and in the time pattern of that rate. The authors advance a number of explanatory hypotheses about the significance of their findings. Originally published in 1960. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.