Proceedings of the American Academy of Arts and Sciences. 

 Vol. XLIV. No. 25. — July, 1909. 



CONTRIBUTIONS FROM THE RESEARCH LABORATORY OF 



PHYSICAL CHEMISTRY OF THE MASSACHUSETTS 



INSTITUTE OF TECHNOLOGY. — No. 42. 



THE PRINCIPLE OF RELATIVITY, AND NON- 

 NEWTONIAN MECHANICS. 



By Gilbert N. Lewis and Richard C. Tolman. 



