A Duo-Art is a Themodist with control from the roll.  It has
Accompaniment and Theme regulators, usually an electric pump,
and definitely a tracker bar with the eight expression level holes
and two Theme control holes.  The hand control levers may be similar
on various Duo-Art and Themodist pianos, but without the Duo-Art
tracker bar and regulators it is definitely not a Duo-Art.

Don't despair, a Weber Themodist is a wonderful instrument if
you take out the vacuum cleaner motor and play it the way it
was intended.

Best regards,
Spencer Chase
spencer@spencerserolls.com