Einstein's comprehensive 1907 essay on relativity, part III, H.M. Schwartz, Am. J. Phys. 45(10), October 1977
This is the concluding part of the English rendition of Einstein's 1907 essay on relativity, of which part I appeared n the June 1977 issue of this Journal and part II in the September 1977 issue. It consists of a direct translation of the last part of the essay, part V, entitled "Principle of Relativity and Gravitation," and a few added footnotes.