The nebular hypothesis was not a scientific induction, but cosmic philosophy. Propounded by Swedenborg and Kant, it was given mathematical form by Laplace in a tentative way. It has been called the grandest conception of the human mind, and, for the eighteenth century, it might have been regarded as good science. It fails, however, to meet the requirements of a modern scientific hypothesis because it does not explain all the facts. But in the absence of any rival theory it has held possession of the field, and has been more generally accepted on insufficient basis than any other conception in scientific philosophy. The time has come for judgment and probable condemnation of the old hypothesis. The formulation of a new and better hypothesis by an honored Fellow and former President of this Society will be recognized in the future as opening a new epoch in earth science and as . . .