Work to repair a collapsed ceiling at the Marion Natural History Museum will go out to bid after engineers make their specifications for the job, said Town Administrator Paul A. Dawson. The ceiling collapsed July 23 when the museum was closed and no one was inside. The cause of the collapse was probably the age of the building, which dates to the 1870s, and stress in the plaster ceiling. Museum programs are still taking place, but not in the museum, which remains closed, Dawson said. A local contractor has volunteered to do the repairs at a reduced rate, but Dawson said state procurement laws must be followed, and the project will go out to bid.