[13] Letter from Frank Duryea to David Beecroft, November 15, 1924; copy in Museum files.
[14] Letter from Charles Duryea to C. W. Mitman, March 21, 1922; copy in Museum files.
[15] See "history" ([footnote 7]), p. 6.
[16] Duryea, op. cit. ([footnote 5]), p. 8.
[17] Copy of letter in Museum files.
[18] Duryea, op. cit. ([footnote 5]), p. 12.
[19] Letter from Frank Duryea to Charles Duryea, November 3, 1893, states that the engine could be run at 700 as well as 500 rpm. Copy in Museum files.
[20] Duryea, op. cit. ([footnote 5]), p. 14. Also in letter from Charles Duryea to C. W. Mitman, January 11, 1922; copy in Museum files.
[21] Letter from Charles Duryea to C. W. Mitman, January 11, 1922; also letter from Frank Duryea to David Beecroft, November 15, 1924. Copies in Museum files.
[22] Letter from Charles Duryea to F. A. Taylor, December 5, 1936, says he "thought" they had five teeth. Copy in Museum files.