CPH to Hopkins, Dec. 19, 1872, LB, 3:177, box 21, Hopkins Collection.
Goldsmith and Hart (sic) CPH, Oct. 22, 1878, CPH Papers, ser. 1, r. 15.
Menahem Blondheim, News over the Wires: The Telegraph and the Flow of Public Information in America, 1844-1897 (Cambridge: Harvard Univ. Press, 1994), 98-99, 108-9, 191.
Richard John, Network Nation: Inventing American Telecommunications (Cambridge: Harvard Univ. Press, 2010),145-46.
Blondheim, News over the Wires, 172, 191.
Hopkins to CPH, Nov. 28, 1872, CPH Papers, ser. 1, r. 5.
Blondheim, News over the Wires, 149, 165, 175.
CPH to Hopkins, March 31, 1876, LB, 8:135, box 23, CPH to Stanford, Jan. 30, 1874, LB, 6:121, box 22, Hopkins Collection.
Adams to Perkins, Sept. 8, 1885, UP, PO, OC, vol. 29, ser. 2, r. 25.