1 Waring (1833–98), of Newport, Rhode Island, was a Union Civil War veteran, agriculturalist, and sanitary engineer who wrote for the Atlantic Monthly on horses, military life, and fox hunting, as well as his professional specialties. His next Atlantic contribution, “The Sanitary Drainage of Houses and Towns,” ran from September through November 1875. He also wrote for Scribner’s Monthly, and issued a collection of sketches, Whip and Spur, through James R. Osgood in 1875.

2 Although Waring had attended the Atlantic contributors’ dinner on 15 December 1874, he might not have met Clemens then. Howells’s letter of 19 July seems to introduce him to Clemens for the first time (13 July 75 to Howells, n. 5). Doubtless he had called at Howells’s suggestion.

3 See pp. 521–23.