a brass reading bell that compels all footsteps in its building to be heard only as whispers for the next hour after it is rung.

The bell is of a common service pattern and bears no maker’s mark. When struck once with its own striker within an enclosed building, all footfalls made under that roof for the next sixty minutes register as a whisper regardless of footwear, gait, or surface. The effect extends to stair treads, ladders, and raised platforms. No other sound is reduced. Dropped objects, doors, and speech remain at ordinary volume. The bell itself gives a normal report when rung, and does not repeat the whispering quality. The interval is stable to within one minute. Attempts to shorten the period by repeated ringing lengthen it in regular increments of one hour per strike. The effect does not occur in the open air. It persists across interior walls and locked rooms, but does not extend to adjacent structures connected only by covered walkways. The bell shows accelerated tarnish when employed more than twice in a day.