The Electrician (London), March 31, 1922, page 396:

Wireless  Notes.

    In a letter to the "Times," Mr. A. A. Campbell Swinton states that, in addition to DAVID  HUGHES'  NOTEBOOKS, containing an account of his experiments in wireless telegraphy in 1879, recently bequeathed to the British Museum, the Museum has even more recently acquired a further set of these notebooks, containing Hughes' own illustrated account of his invention of the microphone. Still more interesting, he states, is the fact that a search, suggested by himself to Colonel H. G. Lyons, of the Science Museum, made amongst the contents of a room full of Hughes' personal effects that for the last twenty years have been stored in a furniture repository in London, has revealed the existence of a number of electrical instruments, coniprising the original first microphones invented by Hughes, and the actual apparatus with which he made his early wireless experiments, all obviously constructed with his own hands. The several instruments can easily be identified by the illustrated descriptions in the notebooks.
    The collection is on view in the Western Hall of the Science Museum, South Kensington.