The Sherlock Holmes Society of London was born in 1951, founded by five of the enthusiasts who created the great Sherlock Holmes Exhibition.
You can read that story elsewhere on this website, under “About the Society”.

There have been other exhibitions devoted to the Great Detective – such as Sherlock Holmes: The Man Who Never Lived and Will Never Die at the Museum of London, and The International Exhibition of Sherlock Holmes – but this was the first on such a scale, and it has never been surpassed. In The Exhibitionists: The Baker Street Journal Christmas Annual 2018, Mattias Boström and Nicholas Utechin wrote of its triumphant run in London, and its subsequent rather less successful period in New York.

Nearly all the exhibits were loaned, by individuals (artists, collectors, members of Arthur Conan Doyle’s family), by libraries, by publishers, and others. So what became of them after the Exhibition closed?

Nicholas Utechin, the Society’s official Historian, has devoted a great deal of time and energy to investigating that little mystery. The result is “Extant Exhibits: The Remains of 1951”, published in the Platinum Jubilee Supplement, which was issued with the Winter 2021 number of The Sherlock Holmes Journal. There are, no doubt, many who’d like to read Nick’s article, but don’t have access to the Journal.

They – and you – can read it here:
Extant Exhibits by Nicholas Utechin