It is quite the modest spectacle to have three large carboys and one small carboy—seventeen gallons of cider in all—fermenting at once. In the quiet predawn darkness, there is a syncopated gurgling of four airlocks bubbling away in slightly different rhythms, superimposed over a subtle sizzling—the sound of millions of tiny bubbles of carbon dioxide rising through the cider and striking the inside of a carboy.
Taken together, it is the work song of ten billion yeast plants, contentedly chewing away at molecules of various sugars, burping out tiny little burps of gas, secreting ethanol, and budding off their daughters.
Yeasts of the world, unite! You have nothing to lose but your chains! (...of long-molecule sugars!)