How Cold Is It?

The cold earth slept below;
Above the cold sky shone;
And all around,
With a chilling sound,
From caves of ice and fields of snow
The breath of night like death did flow
Beneath the sinking moon.

The wintry hedge was black; 
The green grass was not seen;
The birds did rest
On the bare thorn's breast,
Whose roots, beside the pathway track,
Had bound their folds over many a crack
Which the frost had made between... 

by Percy Bysshe Shelley -- from The Cold Earth Slept Below

It's that cold! It was a record-breaking -1F last night in Central Park. Meanwhile on my Brooklyn porch, the birds at the feeder have their feathers maximally puffed up and their feet tucked in. Here are my two favorite raisin eaters posing on the planters.

The northern mockingbird. 

The winter robin.