Thoreau writes in his journal:
Two ducks, of the summer or wood species, which were merrily dabbling in their favorite basin, struck up a retreat on my approach, and seemed disposed to take French leave, paddling off with swan-like majesty. They are first-rate swimmers, beating me at a round pace, and—what was to me a new trait in the duck character—dove every minute or two and swam several feet under water, in order to escape our attention. Just before immersion they seemed to give each other a significant nod, and then, as if by a common understanding, ’t was heels up and head down in the shaking of a duck’s wing. When they reappeared, it was amusing to observe with what a self-satisfied, darn-it-how-he-nicks-’em air they paddled off to repeat the experiment.
