Nathanael's Poem
Nathanael's poem, which he writes concerning his prediction of Coppelius's impact on his life and his and Clara's relationship, is vivid and dreamlike in its imagery. As a poem, it encapsulates Nathanael's strong emotions as he experiences the darkness of mental illness and obsession. As a literary device, it also foreshadows events that happen around the climax of the story, such as Olimpia's eyes burning Nathanael's chest (though in his poem it is Clara's eyes that do so).
Coppelius's Description
Nathanael, in his first letter, describes Coppelius's appearance and actions with childish vividness laced with indignance and disgust. This same childish vividness permeates the entire story and at times makes it difficult for the reader to parse whether Nathanael's perceptions are unduly swaying the narrative, leading to the story's fantastic nature. In any case, the description of Coppelius provides the first tangible blurring of the man with something more monstrous, both in appearance (his nose is described as beaky, fitting with the image of the Sandman with a beak to peck out eyes) and he is supposedly callous enough to take actions purely for the pleasure of upsetting young Nathanael and his siblings. Furthermore, the detail used to describe not only Nathanael's reactions, but also all of his siblings' reactions to the man strengthens the case for some basic level of reality in Nathanael's story.
The Glasses Scene
The scene in Nathanael's room in which Coppola attempts to sell him glasses (leading to Nathanael's purchase of the spyglass and fascination with Olimpia) is one of the most dramatic and vividly written in the story. The writing again blends Nathanael and the narrator's perceptions of the story, and the vividness of Nathanael's perception of eyes within the eyeglasses makes it difficult to parse the supernatural from the insane, creating a strong moment of the fantastic. As is the case throughout the story, much of the vividness comes from charged sensory emotions, as in: "...their flaming eyes sprang to and fro ever more wildly, darting their blood-red rays into Nathanael's breast."
Mental Illness
The status of Nathanael with regard to mental illness, or madness, within the story is what creates much of the fantastic effect. Hoffmann creates and strengthens this sense of fantastic ambiguity and instability through intense imagery of Nathanael's madness. In the poem Nathanael writes and reads for Clara, he speaks of black hands reaching for him and eyes burning into his chest, an image that is made real later in the story (if one trusts the story as told by the narrator). Another good example of Nathanael's vivid madness is his final fit, brought on by seeing Clara in the spyglass: "A convulsion ran through his every vein, he stared at Clara in deathly pallor, but an instant later rivers of fire were glowing and sparkling in his rolling eyes, and he uttered a horrible bellow, like a tormented animal; then he sprang aloft and cried in a piercing voice, interspersed with hideous laughter..." This imagery demonstrates the intensity and suddenness of these fits.
