Get out the microscope, because we’re going through this poem line-by-line.
Line 13
Then chase itself down Hill —
- Freed from the tunnel, the train eagerly goes downhill. This line has a light, playful quality. (We can't help but picture a cute puppy chasing its tail.)
- It's also like a riddle: What can chase itself?
- Answer: a train made up of multiple cars, each one following the engine down the hill.
Line 14
And neigh like Boanerges —
- The creature lets out a rumbling cry, or "neigh," which reminds us of its horse-like qualities from the first lines.
- The speaker compares it to Boanerges, a Biblical name that means "son of thunder," and generally refers to a booming, loud preacher or public speaker.
Lines 15-17
Then — punctual as a Star
Stop — docile and omnipotent
At its own stable door —
- In these lines the speaker uses a simile. She says that the train is "punctual as a star."
- Stars, of course, show up in the sky at a specific time each night. It sounds like the speaker is suggesting that the train is as punctual as nature.
- At last, the creature stops, right on time, and placidly returns to its home, or "stable" (another horse reference to bear in mind).
- In these final lines, the speaker also describes the train as "docile and omnipotent." This characterization again gives humanlike (or even super-humanlike) qualities to the train. On the one hand, the train is "docile," or submissive. On the other hand, it's "omnipotent," or all-powerful.
- The train, in other words, is a complicated thing with many qualities and many characteristics. And it's all pretty new to the speaker, so maybe she's still not quite sure what to make of it.