Would you please tell me, if there are an specific idea about the difference between Hydraulous’ (water organ) and modern keyboards? I know that they existed long time ago in the Greek civilization. I wonder what was the first asymmetrical layout keyboard, and if it changed until the organ’s keyboards. The actuals, they seem too appropriate to fingering melodies, and touching any music. They seem irreplaceable. I like to know about an specific historical events. Thank you.