George Mougenot published a monograph on this instrument in 1892, entitled "Description du superbe violon de Stradivari, dit 'le Mercure'".
How Many Strads, Ernest N. Doring, Ernest N. Doring, William Lewis & Son, Chicago, 1945
"The violin first appeared before the public in the exhibition of musical instruments at the Royal Aquarium, Westminster, in October, 1892, where it was shown under the fantastic title of 'The Mercury,' by Messrs. Paul Bailly and Son, the French violin-makers who have, we understand, recently left this country."
Observations, E. Polonaski (editor), The Violin Times
"The "Mercury" has never been repaired, save as to the usual changes of neck and bass-bar, necessary in all the old fiddles by
reason of the rise in pitch. Early in the present century this magnificent violin was in the possession of the Viscount de Bioley, an
eminent manufacturer at Verviers in Belgium. He left it to his grandson, Count Van der Straeten-Ponthoz, of Brussels, who was not a violinist, and for a long time no one played upon the instrument but the late Prince de Chimay, who alone had access to it, and he but seldom. M. Georges Mougenot, violin maker to the Brussels Conservatoire, was at length called in to examine the violin ; he at once offered to buy it, and it passed into his keeping. This unique specimen, free from the ruinous butchery of the repairer, was at length bought by Mr. J. Williams, of Walsall, who is the happy possessor of one of the finest violins in the world."
The 'Mercury' Strad, The Strad, 1893, London