Blue shadows on the snow.

January 4. 

A clear, cold day. 

P. M. — To Walden to examine the ice. 

I think it is only such a day as this, when the fields on all sides are well clad with snow, over which the sun shines brightly, that you observe the blue shadows on the snow. I see a little of it to-day. 

December 29th there were eight or ten acres of Walden still open. That evening it began to snow and snowed all night, and the remainder of the pond was frozen on that and the succeeding night. 

But on January 1st I was surprised to find all the visible ice snow ice, when I expected that only the eight or ten acres would be; but it appeared that the weight of the snow had sunk the ice already formed and then partly dissolved in the water, which rose above it and partly was frozen with it. The whole ice January 1st was about six inches thick, and I should have supposed that over the greater part of the pond there would be a clear ice about two inches thick on the lower side, yet, where I cut through near the shore, I distinguished two kinds of ice, the upper two and a half inches thick and evidently snow ice, the lower about four inches thick and clearer, yet not remarkably clear. 

Some fishermen had, apparently by accident, left two of their lines there, which were frozen in. I could see their tracks leading from hole to hole, where they had run about day before yesterday, or before the snow, and their dog with them. And the snow was stained with tobacco-juice. They had had lines set in two or three distant coves. 

They had, apparently, taken no fish, for they had cut no well to put them in. I cut out the lines, the ice being about an inch thick around them, and pulled up a fine yellow pickerel which would weigh two pounds or more. At first I thought there was none, for he was tired of struggling, but soon I felt him. The hook had caught in the out side of his jaws, and the minnow hung entire by his side. It was very cold, and he struggled but a short time, not being able to bend and quirk his tail; in a few minutes became quite stiff as he lay on the snowy ice. The water in his eyes was frozen, so that he looked as if he had been dead a week. 

About fifteen minutes after, thinking of what I had heard about fishes coming to life again after being frozen, on being put into water, I thought I would try it. This one was to appearance as completely dead as if he had been frozen a week. I stood him up on his tail without bending it. I put him into the water again without removing the hook. The ice melted off, and its eyes looked bright again; and after a minute or two I was surprised by a sudden, convulsive quirk of the fish, and a minute or two later by another, and I saw that it would indeed revive, and drew it out again. 

Yet I do not believe that if it had been frozen solid through and through it would have revived, but only when it is superficially frozen. This reminded me of the pickerel which I caught here under similar circumstances for Peter Hutchinson, and thrust my mittened hands in after. When I put this pickerel in again after half an hour, it did not revive, but I held it there only three or four minutes, not long enough to melt the ice which encased it. 

Another man had passed since the last snow fell, and pulled up at least one of the lines. I knew it was to-day and not yesterday by the character of his track, for it was made since the stiff crust formed on this snow last night, a broad depression cracking the crust around; but yesterday it was comparatively soft and moist. 

It is snapping cold this night (10 P. M.). I see the frost on the windows sparkle as I go through the passageway with a light.

H. D. Thoreau,  Journal,  January 4, 1856

Yet I do not believe that if it had been frozen solid through and through it would have revived. See March 20, 1857 ("When I began to tell him of my experiment on a frozen fish, [Agassiz] said that Pallas had shown that fishes were frozen and thawed again, but I affirmed the contrary, and then Agassiz agreed with me.")

I think it is only such a day as this, when the fields on all sides are well clad with snow, over which the sun shines brightly, that you observe the blue shadows on the snow. See February 10, 1855 ("I go across Walden. My shadow is blue. It is especially blue when there is a bright sunlight on pure white snow. ")and note to January 6, 1856 ("Now, at 4.15, the blue shadows are very distinct on the snow-banks.")

I see the frost on the windows sparkle as I go through the passageway with a light. See December 28, 1859 ("In the morning the windows are like ground glass (covered with frost), and we cannot see out.");  February 5, 1855 ("It was quite cold last evening, and I saw the scuttle window reflecting the lamp from a myriad brilliant points when I went up to bed.")

in addition

to my solitude

frost on the window

Issa