Note 5 — Chapter I

The udometric measurements of Belgrand, reported in the Annales Forestières for 1854, and discussed by Vallès in chap. vi of his Études sur les Inondations, constitute the earliest, and, in some respects, the most remarkable series known to me, of persevering and systematic observations bearing directly and exclusively upon the influence of human action on climate, or, to speak more accurately, on precipitation and natural drainage. The conclusions of Belgrand, however, and of Vallès, who adopts them, have not been generally accepted by the scientific world, and they seem to have been, in part at least, refuted by the arguments of Héricourt and the observations of Cantegril, Jeandel, and Belland. See chapter iii: The Woods.