Scrying Glasses, otherwise known as seeing-eye glasses, are magical items that allow the possessor to see people, items, or anything else over great distances. The item itself doesn't necessarily have to be a glass, it can be anything with a reflective surface, i.e. a metallic disk, buffed until it shines. The item used is normally shiny by itself, although it does not have to be fancy to be made into a scrying glass.
Mechanics EditLike most magical items, a proper scrying glass is created by simply entrapping a spirit within a glass. A scrying glass, therefore, would require some form of smooth, visible surface for seeing visions in. The spirit, usually merely an imp, appears within the surface of the glass for the magician to relay instructions to, and then materialises wherever the magician orders it to. (The only time that this such materializing is shown is when the imp appears between a curtain of golden sparks resembling faerie dust after locating Bartimaeus). The spirit has a limited range to do this, as it is attached to a spirit/astral cord (the other end of which is tied to the glass), through which its vision and hearing can be relayed through the glass to the magician (The sound in the only shown scrying glass is merely the imp saying what the focus of the glass was saying, not actually relaying the person's voice). In cases where the magician does not wish to directly see what the spirit is viewing, the spirit is able to replay what they have seen and heard, and even zoom in, freeze-frame, and enhance the volume. They cannot however, show anything they had not heard or seen at the time.
It is assumed that the spirits employed in the use of scrying glasses are similar in role to those who use viewing globes.
The scrying glass has several deficiencies, most notable are the following:
- The insight gained by the glass is dependent entirely upon the spirit, meaning that if it can't see what one is looking for, the owner will not able to see it either.
- The information given can be a trick of the spirit within, meaning the results of what one sees can be false. Obvious attempts at this are usually swiftly countered with reprimand.
- The spirit is visible and tangible on higher plains, meaning other spirits, and to a lesser extent through magician's lenses, the spirit is visible, and vulnerable to attack. Worse still, a spell exists that allows another magician to astral-project from their body and follow the spirit cord to the owner of the glass, thus finding out the identity of the spy without bringing harm to the magician.
- The glass can be stolen (like what happened to Nathaniel's in the first book), and the user/creator would have to get it back by themselves.
- The spirit, if discovered, can be destroyed, rendering the glass useless.