Note 68 — THE ECONOMICAL NATURE OF PHYSICAL INQUIRY.[60]

I have represented the point of view here taken for more than thirty years and developed it in various writings (Erhaltung der Arbeit, 1872, parts of which are published in the article on The Conservation of Energy in this collection; The Forms of Liquids, 1872, also published in this collection; and the Bewegungsempfindungen, 1875). The idea, though known to philosophers, is unfamiliar to the majority of physicists. It is a matter of deep regret to me, therefore, that the title and author of a small tract which accorded with my views in numerous details and which I remember having caught a glance of in a very busy period (1879-1880), have so completely disappeared from my memory that all efforts to obtain a clue to them have hitherto been fruitless.