in Thoreau’s Journal:

You take your walk some pretty cold and windy, but sunny March day, through rustling woods, perhaps, glad to take shelter in the hollows or on the south side of the hills or woods. When ensconced in some sunny and sheltered hollow, with some just melted pool at its bottom, as you recline on the fine withered sedge, in which the mice have had their galleries, leaving it pierced with countless holes, and are, perchance, dreaming of spring there, a single dry, hard croak, like a grating twig, comes up from the pool. Such is the earliest voice of the pools, where there is a small smooth surface of melted ice bathing the bare button-bushes or water andromeda or tufts of sedge; such is the earliest voice of the liquid pools, hard and dry and grating. Unless you watch long and closely, not a ripple nor a bubble will be seen, and a marsh hawk will have to look sharp to find one. The notes of the croaking frog and the hylodes are not only contemporary with, but analogous to, the blossoms of the skunk-cabbage and white maple.

Are not March and November gray months?

Men will hardly believe me when I tell them of the thickness of snow and ice at this time last year.