What is a figure of speech in the poem "The Splendour Falls" by Lord Alfred Tennyson?
A main technique Tennyson uses is personification, which is where you give inanimate objects or ideas human-like traits. For example, he says that "the long light shakes across the lakes." Light does not shake; saying that it does makes it seem alive, with movement and intention, like a living thing. He also says "the wild cataract leaps in glory," giving another life-like motion to an inanimate thing. Near the end, he says to set "the wild echoes flying," another example of personification.
Personification helps elements of nature, and even emotions, have more depth and layer. It helps things that mormally are quite flat and still seem to be alive, which adds layer and profundity to what could be a rather dull scene or description. Tennyson uses it quite well to make it seem like the light and sounds of the poem are in themselves alive and vibrant participators in the action. I hope that helped; good luck!