Operators · Arcane working · Artifice
Gate Mind
Keeper of Bolts
Vault doors, guarded gates and lift mechanisms; built into the door or the wall beside it
A lock-control device built into a great door or the wall beside it, which compares the seal and the word it is given with those it was set to accept, and works the bolts and lifts accordingly. It is the reason a vault has no keyhole.
The guarded vaults of Cambridge and the strong rooms of the great London houses open on a gate mind rather than a key. A seal is laid against it, a word is given, and its rings turn and compare; if they match, the bolts withdraw and the lift rises. If they do not, nothing happens, and a second wrong attempt may bring something else. It is the most trusted of all devices because it does exactly one thing and has no reason to do anything else.
Its weakness is the one every lock shares. A gate mind whose seal and word are both lost cannot be opened by anybody, and there are vaults under Cambridge that have stood shut for a century on that account, with a gate mind still faintly lit in the wall beside them. The Collegium has been asked to open them and has declined, and the reason it gives is that it does not know what was set to happen at the second wrong attempt.
As witnesses describe it
Either a great round door set with concentric rings of glowing blue-white runes and lenses, or a tall panel of dark stone and iron beside a passage, with a single amber core. When it compares a seal, its rings turn and brighten; a gate mind on reserve shows only one small light.
