A television program celebrating the life of St. John Clarke starts and ends with “St. John Clarke’s portrait (butterfly collar, floppy bow tie) painted by his old friend, Horace Isbister, R.A.” [HSH 39/40 ].
Isbister, whom Powell introduced in QU, has a number of appearances in Dance [The Walpole-Wilson Portraits (BM), Isbister, The British Frans Hals (AW), At the Isbister Memorial Exhibition (AW), Isbister According to St. John Clarke (CCR), and Outside the Army Council Room (MP)] prior to HSH. Later in HSH, Jenkins mentions a final Isbister portrait, that of Sir Horrocks Rusby in wig and gown, presumably similar to the portrait of Lord Aberavon [HSH 62-3/65]

John Galsworthy
Rudolf Helmut Sauter, 1923
oil on canvas
University of Birmingham;
© the copyright holder. Photo credit: University of Birmingham
from ArtUK.org
John Galsworthy is often mentioned as a model for Clarke, so we offer a portrait of Galsworthy, collar, bowtie , and all. Rudolf Sauter’s (1895-1977) biography does not match Isbister’s: Sauter showed at the Royal Academy but was never elected to membership; he was Galsworthy’s nephew and illustrated the definitive edition of his works. The portrait is worthy of Isbister, competently flattering the sitter, but leaving the viewer minimally informed and unexcited. Other portraits of Galsworthy with collar and bowtie, including those by William Strang R.A. (1859-1921) (lithograph), the caricaturist Sir David Low (1891-1963) (pencil), and various photographers shown at the National Portrait Gallery, do not provide other clues to models for Isbister.
After Jenkins and his friends watched the program, “Members then let off a mild bombshell. He suggested that the friendship with Isbister had been a homosexual one. The contention of Members was that the central figure in an early genre pictures of Isbister’s — Clergyman eating an Apple — was not at all unlike Clarke as a young man, Members advancing the theory that Isbister could have possessed a fetishist taste for male lovers dressed in ecclesiastical costume.” [HSH 40/]
Even with this new clue, we have not been able to find a facsimile of the Clergyman. Like Jenkins and his friends, we will leave Horace Isbister, R.A. still a subject for amused speculation.