in Thoreau’s Journal:

The earliest water surfaces as I remember––as soon as the ice is melted–present as fair & matured scenes, as soft & warm, reflecting the sky through the clear atmosphere––as in midsummer––far in advance of the earth. The earliest promise of the summer––

is it not in the smooth reflecting surface of woodland lakes in which the ice is just melted? The liquid eyes of nature––blue or black or even hazel. Deep or shallow––clear or turbid. Green next the shore the color of their iris.