Note 27 — Chapter IV · OUTLINE OF THE PHYSICAL AGENCIES WHICH LEAD TO SECULAR CHANGES OF CLIMATE.

Connaissance des Temps for 1863 (Additions). Lagrange’s determination makes the superior limit 0·07641 (Memoirs of the Berlin Academy for 1782, p. 273). Recently the laborious task of re-investigating the whole subject of the secular variations of the elements of the planetary orbits was undertaken by Mr. Stockwell, of the United States. He has taken into account the disturbing influence of the planet Neptune, the existence of which was not known when Leverrier’s computations were made; and he finds that the eccentricity of the earth’s orbit will always be included within the limits of 0 and 0·0693888. Mr. Stockwell’s elaborate Memoir, extending over no fewer than two hundred pages, will be found in the eighteenth volume of the “Smithsonian Contributions to Knowledge.”