William Wordsworth: Incident (Characteristic of a Favourite Dog)

On his morning rounds the Master
Goes to learn how all things fare;
Searches pasture after pasture,
Sheep and cattle eyes with care;
And, for silence or for talk,
He hath comrades in his walk;
Four dogs, each pair of different breed,
Distinguished two for scent, and two for speed.

See a hare before him started!
—Off they fly in earnest chase;
Every dog is eager-hearted,
All the four are in the race:
And the hare whom they pursue,
Knows from instinct what to do;
Her hope is near: no turn she makes;
But, like an arrow, to the river takes.

Deep the river was, and crusted
Thinly by a one night's frost;
But the nimble Hare hath trusted
To the ice, and safely crost; so
She hath crost, and without heed
All are following at full speed,
When, lo! the ice, so thinly spread,
Breaks—and the greyhound, Dart, is overhead!

Better fate have Prince and Swallow—
See them cleaving to the sport!
Music has no heart to follow,
Little Music, she stops short.
She hath neither wish nor heart,
Hers is now another part:
A loving creature she, and brave!
And fondly strives her struggling friend to save.

From the brink her paws she stretches,
Very hands as you would say!
And afflicting moans she fetches,
As he breaks the ice away.
For herself she hath no fears,—
Him alone she sees and hears,—
Makes efforts with complainings; nor gives o'er
Until her fellow sinks to re-appear no more.

Composed 1805, published 1807 (i.e. shortly before the start of Wordsworth’s notorious decline as a poet). Despite the sentimentality, there's a tougher note of cruelty that kept this poem out of the Victorian / Edwardian canon for schoolchildren.