hydro levels

Everything in the down position.

Well, that explains it. Hydro…

Hydro generally only refers to water, as in power generation from a water source.

have an 80's MTD riding mower marketed as a (Co-Op Hydrostatic)

 Don't think I'll top her up with water tho. Think the Hydro will make it static… 

seriously when used with static,     Hydrostatic drive is the correct name for a hydraulic infinitely variable drive system   right??..maybe because water is not compressible the (hydro)  part was adopted years ago?? But thought I'd also seen Hydrastatic..?? Tinbender got me thinking

If I remember correctly, the second or third labor of Hercules was to kill Hydra. And thusly brings forth poetic justice because you will never find a Hydramatic© transmission behind a Hercules engine.

Hydro, from Greek hudōr = water.

The term hydrostatic literally translates to still water. With static being systems or solutions in equilibrium – not moving.

But for symantics sake, the term hydrostatic refers to the transfer of energy from flow and pressure, not from the kinetic energy of the flow.

Fwiw, water is just as compressible as oil, practically speaking, but lacks lubricating properties found and formulated into hydraulic oils.

Thanks for the information Bob,  it's interesting how the Greeks still influence modern society to this day

This is the evolutionary process. We are all part of it.