wouldn't it be easier to just have slaves turn the gears for you rather than use that complicated setup with the liquid aether (probably hard to get) and special leeches (probably hard to keep alive) on a live mage (who probably wants nothing more than to kill the leeches...and whoever shoved them in the barrel...)? although I suppose that setup is lighter weight than at least two sets of burly slaves one set spinning the gears away and the other set(s) resting until it's their turn again...or just, ya know, go pure magi-mechanical and use a different mana fuel without living parts required?