The Old Man's Eye
The old man's eye is blue with a "film" or "veil" covering it. This could be a medical condition, like a corneal ulcer, but symbolically it means that the characters have issues with their "inner vision" – what's commonly known as one's outlook on the world. They are stuck. Everything is obscured for them. Our reading of the story is likewise filtered through this hazy eye, causing at least some confusion and frustration with the text.
The eye also does some pretty weird stuff. It seems dull and unseeing – yet, it has strange powers. It makes the narrator's blood run cold. It "chill[s] the very marrow in [his] bones" (6). After hiding the old man's body, the narrator "replaced the boards so cleverly, so cunningly, that no human eye – not even his [the old man's] – could have detected any thing wrong" (8). Interesting. That statement implies that at some point the eye could see hidden or secret things.
The eye also seems to have a bodyguard, the heart. When the narrator trains the beam on the open eye, it causes the heart to beat an alert. When the policemen are there, the heart beats loudly to alert the cops – so the eye can again see and be seen.
The narrator is fixated on the "vulture eye" aspect of the old man's eye. He brings it up three times. Vultures prey on the sick or dead, and they gorge themselves to the point of stupor. Whether or not the old man is a vulture-like person, we can't know. But that's what he symbolizes to the narrator. If vultures prey on the dead and almost dead, and the narrator is afraid of the "vulture eye," does this mean the narrator is dead or almost dead?
The narrator mentions a "watch" four times in the story. A watch is a visual and auditory representation of time. The watch watches time, and tells tales of time. Time can also be said to be watching death, up ahead in the distance. Each tick of the watch symbolizes a movement closer to the inevitable death that all humans face. Poe presents this subtly in the story's first mention of the watch: "A watch's minute hand moves more quickly than did mine" (4).
This of course is on the eighth night. Here the narrator compares himself to a watch, a watch watching the old man's death. The narrator steals time's power as an agent of death. The narrator literally controls the time of the old man's death. He's a walking "death watch."
This metaphor/word play becomes more explicit in the second mention of time in the story: "He was still sitting up in the bed listening; – just as I have done, night after night, hearkening to the death watches in the wall" (4).
This is a mystifying line, until we know that "death watches" are kind of beetle. Death watch beetles live inside walls, and bang their heads on said walls to attract mates (source). Poe might not have known this was a mating call, and was likely referring only to the popular belief that the banging is a countdown to someone's death. Then again, maybe he did know. Intentionally or not, this odd moment in the novel juxtaposes sex and death in a way that would have made Sigmund Freud proud. In Beyond the Pleasure Principle Freud theorized that death and sex are intimately and intricately intertwined.
Now for the second and third mentions of "watch" in the story:
[N]ow, I say, there came to my ears a low, dull, quick sound, such as a watch makes when enveloped in cotton. (6)
It was a low, dull, quick sound – much such a sound as a watch makes when enveloped in cotton. (9)
The old man's heart is also a watch, as we see in these almost identical passages. It both watches and counts down the time leading up to the man's death (first passage). Then the heart/clock becomes a zombie of sorts (second passage). It resurrects itself so it can tell about the time (of death) it watched, in a sense taking time back from the narrator. Pretty clever.
This lantern is pretty cool. You can burn a candle or oil in it (doesn't say which in the story), but it has hinged panels that can be adjusted to let in as much or as little light as you want. The narrator keeps most of the light hidden, only allowing one "ray" to escape. This lantern is the narrator's weapon against the old man's eye. That's what we see on the eighth night – the lantern and the eye in a stare-down. It also suggests that sometimes there is light hiding in the darkest places. If we can figure our how to get our lanterns open, we can see it. Can you find any hidden light in this dark tale?
The Bed and Bedroom
The bed in "The Tell-Tale Heart" symbolizes the opposite of what beds and bedrooms should be about. The narrator violates all bedroom etiquette, by exploiting the vulnerability of one who is sleeping. We are perhaps most vulnerable in bed, and we sleep well when we feel safe in our bedrooms. Poe turns the symbol of the bed on its head. The narrator uses the bed as weapon to snuff out the old man. And since the bed is the murder weapon, it's logical that the bedroom is the burial place. Creepy.