Maryland officials are preparing to tear down a more than 130-year-old prison that was closed in 2007 after a string of violent incidents.Inmates are taking apart the Maryland House of Corrections piece by piece. Officials with the prison system said the method of deconstruction is expected to save millions of dollars and that inmates have recovered $80,000 worth of materials so far.The prison will be open for public tours on Aug. 4 and 5 before the deconstruction ramps up. On Saturday, it was open to current and former corrections officers.The prison held some of Maryland's most violent inmates for 128 years. It was shut down after an especially violent year in which two correctional officers were stabbed, one fatally.