The details of Johnston's early education are not known, but he was definitely proficient with the written English language and other topics; surviving letters about his reenlistment and pay issues were prepared in his handwriting, and though they contain minor spelling errors, they are highly literate, and display a clear grasp of grammar, punctuation, and the ability to communicate detailed information clearly and concisely. He attended
Norwich University from 1866 to 1868, but left without graduating. In 1867 Johnston, competed for a position at the
United States Military Academy, but was not selected. In the late 1860s, Johnston also played in St. Johnsbury's town band. He moved to
Charlestown, Massachusetts in the late 1860s, where he married Nellie Murphy on March 1, 1870. William Henry (born 1872), Mary (born 1874), Charles Cyril (born 1876), and Leo Francis (born 1878). The family lived at 65 Tremont Street and Johnston worked as a machinist. The drum was subsequently turned over to the curator of the Civil War relic room at the
Massachusetts State House. News accounts about Johnston's drum caused newspaper editors in Vermont to attempt to locate Johnston. Johnston's father, by now a resident of
Colorado, visited St. Johnsbury later in May and was the source for newspaper stories which indicated that Johnston was a resident of Charlestown before becoming a member of the "naval service," which William Johnston stated had been his son's occupation for several years.
United States Navy records for the period do not provide details on "William Johnston" or "William Johnson" that can be conclusively identified as Johnston, raising the possibility that he served under an assumed name or in a support role that would not have required him to be identified on Navy muster or pay rolls, such as continuing to work as a machinist. The State House was later searched, but the drum was not located, and subsequent attempts to find it have been unsuccessful. In 1890, a newspaper account indicated that Johnston's father had requested that the plaque from Johnston's drum be sent to him because Johnston was no longer alive. Johnston was not dead in 1890, as evidenced by the Chelsea city directories for the late 1880s, 1890s, and early 1900s, which listed him as a "mariner" and then a "master mariner" indicating that he pursued a career as a merchant sailor and ship captain. ==Later life==