Thoreau's Journal: 29-Apr-1856
Do not sail well till I reach Dove Rock, then glide swiftly up the stream. I move upward against the current with a moderate but fair wind, the waves somewhat larger, probably because the wind contends with the current. The sun is in my face, and the waves look particularly lively and sparkling. I can steer and write at the same time. They gurgle under my stern, in haste to fill the hollow which I have created. The waves seem to leap and roll like porpoises, with a slight surging sound when their crests break, and I feel an agreeable sense that I am swiftly gliding over and through them, bound on my own errands, while their motion is chiefly but an undulation, and an apparent one. It is pleasant, exhilarating, to feel the boat tossed up a little by them from time to time. Perhaps a wine-drinker would say it was like the effect of wine.