Hoar-frost
This morning I walked to campus through the remains of a thick winter fog, the kind of fog where you can barely see the sun as a dull white disc trying to burn through. It was below freezing, and the fog had left a fine layer of frost on everything. The smaller the object, the more noticeable the frost: tree trunks didn’t look much paler than usual, but the ends of branches and the undersides of leaves had turned white, as had the stems of a lot of small red berries growing in clusters on an ornamental tree. (The berries themselves were unfrosted.)
By the time I had a chance to go out again, the sun had come out. I ran into a fellow lecturer on the front steps of the building, and she commented on the fog-frost (or frost-fog). She said that first thing in the morning it was so foggy she couldn’t even see the top of our university’s clock tower. But the frost was gone by the time we compared fog notes.
So I went googling for images of fog-derived frost, or hoar-frost. This morning’s weather looked a little like this, but less frosty; or like this, or (my favorite) this. I like this one as well, even though Collegeville never looks this ethereal.
Upon looking it up, I found that the OED distinguishes hoar-frost from rime, thusly: hoar-frost is "a crystalline deposit of ice formed by the sublimation of water vapour," while rime is "a more amorphous deposit formed by the rapid freezing of supercooled droplets of water when they are brought by air currents into contact with a cold surface." I think this morning’s frost was technically rime, but I like the word hoar-frost better. It has an Old English ring to it (no wonder: the OED’s earliest recorded usage for hoar is dated 900). And for some reason I associate it with the opening stanzas of Keats’s "The Eve of St. Agnes," although on looking that up I realize that I must have misremembered. No hoar-frost there. But Keats knew from winter: I don’t know if any other poet has conveyed the sense of the bone-chilling cold of churches in winter as well as he did with that second stanza and the lines "The sculptur’d dead, on each side, seem to freeze, … and his weak spirit fails / To think how they may ache in icy hoods and mails."
(And one more image: Hoarfrost in Concord, Massachusetts, 1899. From the Concord Free Public Library.)
A young photographer here in New York has a series called ‘Snow Pictures,’ of which this is my favorite. I think it fits the description of ‘hoar frost.’