VerseComparison or imageMain quality
53A rock forced down by a torrentPowerful acceleration
54Sliding on smooth rockSleek back and surface
55A boiling cauldronInner energy and turbulence
58A child's spinning topContinuous rapid turning
The four pictures come from different worlds: a violent natural flood, the surface of stone, a household vessel, and a child's game. Each makes a different sensory characteristic of the horse observable.
Translating all of them as “a very fast horse” loses the differentiation of the poem. Better reading identifies the distinct point of resemblance supplied by each image.