Help deciphering a probate record [View all]

I'm looking over my 4x great grandfather's will and probate records. There is a list in his probate of people who owe him money (dated 1842). One person owed by far the largest amount. ($120.00). Written next to this entry it is noted "this note we consider very uncertain as the signer has taken the benefit of the -------act." The handwriting is hard to read. It looks like it could say the mercer act, the mercy act, the miner act.....I can't be sure. I wondered if anyone had heard of some sort of act from that time period that would allow a person to ditch their debt. I believe but am not certain that the person who owes this is a nephew to the man whose will it is. I'm not sure if it would make a difference or not if he's a relative. Any insight will be appreciated. Thx.