MONROE-Manhattan's Merchant's House Museum is in an 1832 townhouse, home to a New York City merchant family for 100 years, filled with the furnishings, clothing, and personal items of the original owners and their descendents. The Monroe Free Library is sponsoring a bus trip to the Merchant's House Museum on Wednesday, April 27. The trip also includes a stop at the South Street Seaport. Tickets are $25. Register at the library or by phone, 783-4411.