July 13 or 14, 1877: Sam traveled to New York [MTLE 2: 94]. He returned to Elmira August 3rd.
August 7, 1877: The Clemens family possibly went to Ithaca, New York for a two-day visit to Hjalmar H. Boyesen and family. They were back in Elmira by Aug. 11.
August 11–14 Tuesday – Sam went to New York, business unknown, and stayed at the St. James Hotel [MTLE 2: 133]. No mention of how long he was there but he was back in Elmira on or around August 18th.