But he was a horse no more - the beasts of George MacDonald

The hero of Lilith has just returned to dream-land, where he is given a moon-horse. (What?):

Nineteen hands he seemed, huge of bone, tight of skin, hard of muscle - a steed the holy Death himself might choose on which to ride abroad and slay.  The moon seemed to regard him with awe; in her scary light he looked a very skeleton, loosely roped together.  Terrifically large, he moved with the lightness of a winged insect. (Ch. 31, "The Old Sexton's Horse")

So the story of Lilith is that a bookish fellow sees a ghost in his library, which leads him to Fairy-land, which is partly ruled by Lilith, Adam's first wife, who turns into a leopardess and steal babies, while the forest children fight the giants, and, let's see.  Anyway, the hero loves his moon-horse, and rides off to hunt the leopardess.  Lilith is a novel of repeated journeys over the same terrain, with variations on each trip.  The horse rushes past every obstacle the hero had previously encountered on foot.  Then the wolves howl and the moon sinks below the horizon:

The mighty steed was in the act of clearing a wide shallow channel when we were caught in the net of darkness.  His head dropped; its impetus carried his helpless bulk across, but he fell in a heap on the margin, and where he fell he lay.  I got up, kneeled beside him, and felt him all over.  Not a bone could I find broken, but he was a horse no more.  I sat down on the body, and buried my face in my hands. (end of Ch. 31)

MacDonald's novels are packed with beasts.  At the Back of the North Wind costars a horse.  In The Princess and the Goblin, the miner boy Curdie battles strange hybrid cave creatures, while in The Princess and Curdie, he gathers his own army, and then uses the special powers of each beast - one, for example, is a giant sphere with a face - to defeat his enemies, much in the manner of Pokémon.  The beasts return in Lilith as monsters - as "a solitary, bodiless head" which springs away with "a rapid rotatory twist," or "a dreadful head with fleshy tubes for hair" and a "great oval mouth" or "a long neck, on the top of which, like the blossom of some Stygian lily, sat what seemed the head of a corpse, its mouth half open, and full of canine teeth" (all from Ch. 40).

For some reason, though, it's the horses that interest me the most.  At the Back of the North Wind is in part a real London novel, set in the world of cabbies and their horses.  The treatment of horses is part of the plot.  MacDonald's novel began to be published nine years before Anna Sewell's Black Beauty (1877), which I last read at least thirty years ago.  Where else can we find this theme?  Perhaps - nay, in all likelihood - you have been leafing through John Stuart Mill's Principles of Political Economy (1848, with many subsequent editions), where in Book 5, Chapter 11 you will find:

The reasons for legal intervention in favour of children, apply not less strongly to the case of those unfortunate slaves and victims of the most brutal part of mankind, the lower animals. It is by the grossest misunderstanding of the principles of liberty, that the infliction of exemplary punishment on ruffianism practised towards these defenceless creatures, has been treated as a meddling by government with things beyond its province; an interference with domestic life. The domestic life of domestic tyrants is one of the things which it is the most imperative on the law to interfere with...

This immediately follows an argument against restricting the labor force participation of women, who are not helpess creatures like children or horses.

I've come a bit far from George MacDonald, but I doubt he would mind.  His fantasies are the sorts of books that are meant to lie in the lap while the reader's imagination wanders through its own dream-land.

Thanks again to my mother for assisting with George MacDonald Week.