It Might Be A Magic Trick,

but it is in fact a musical instrument, 

the photographs are from the Byron collection, but little more information is given on the photo other than “Musical act” pencilled on the back. The unusual contraption depicted was probably the centrepiece of a musical act at Coney Island or at Union Square circa early 1900s,

 but looking further I found this at (Roughly) Daily:

‘Mr. and Mrs. Karsy, an inventive and original “team” on the variety stage, have created a new and extrodinary musical instrument which is known as the Giant Myriophone (Myriphon). It is the work of a genius and when under full swing produces music similar to that of a full string band. Only two persons are required to produce this immense volume of sound. “The Myriophone has the appearance of a large screen, with a number of wheels fitted on the front. These wheels have strings fitted on them and look much like bicycle wheels. They are set in motion by four lusty stage hands concealed in the rear, and the performers who have a small stick of wood in each hand touch the strings, thus making a note, which can be prolonged to any length. The Myriophone consists of twenty-five discs, each with eighty strings, making 2,000 in all. The sounding boards are made of the same wood as is used in pianos. Regular piano strings are used’,

I then found out a little more about this fantastical instrument, above reproduced courtesy of The International Brotherhood of Electrical Workers, (IBEW), where I found this article, what a amazing machine, I just wish someone could have recorded the sounds it made, looking at it I guess it would be a Herculean task to build another, but if some one has a few spare evenings, with winter just a few months away, you could always try to make one in your garden shed or garage!