My guess is it's a telephone bell. If so, it will be designed to run from a 20 Hz sinewave at around 100V. I wouldn't connect it to the mains; the frequency is much too high and it will overheat because the clapper can't move that fast.
I'm not sure whether this will help you, but I designed a circuit to drive a similar bell using a centre-tapped mains transformer in reverse. Here's the schematic. I used a lot of shorthand in the component values; let me know if you want more details. This should give you the general idea though.
Power comes in on CN1. I used about 30V DC unregulated, from a 24VAC transformer with bridge and plenty of smoothing. U3 creates a 12V rail for U1 and U2. U1 oscillates at a higher frequency than the bell clapper moves at; U2 divides the frequency by ten and provides two short pulses at opposite halves of the cycle, which activate MOSFETs Q1 and Q2, which are used as a crude push-pull driver to energise the drive transformer connected to CN2 one way or the other. The transformer was probably something like 110V input, 24-0-24 output. It's connected in reverse, i.e. the secondary is driven from CN2 and the primary is connected to the bell.
You adjust the oscillator frequency for the best efficiency and loudest noise from the bell. Bells can be very loud, and the sound carries a long way. I think they're better than sirens as alarms and alerts.
Let me know if you want to pursue this and I can give more details.
