The Moldova water organ is an interesting design.  Imagine the water
organ designed by Marcus Vitruvius. In his architectural writings from
the 1st century B.C., he describes an organ with "bronze dolphins
holding chains in their mouths" from which the valves hang.  The
cylinder(s) is made of bronze and the entire instrument is mounted on
a wooden base.

He goes on to describe the mechanism, "When the keys, touched by the
hand, drive the sliders forward and draw them back regularly,
alternately stopping and opening the holes, they produce resonant
sounds in a great variety of melodies conforming to the laws of music".

It's hard to tell the exact size of this instrument, but it sounds like
it was fairly large.  More details can be found in "The Ten Books On
Architecture" published by Dover.

Have any replicas been made of this instrument?

Brian Smith