 Through the blackface mask and doing this contorted dance that sort of mimicked or represented the stereotype disfigured black enslaved body, right? I am Matthew D. Morrison. He's a historical musicologist and professor at the Clive Davis Institute of Recorded Music at New York University. He's also the author of the book Black Sound, Making Race and Popular Music in the United States. And when Matthew first finished his book, he had his grandfather read it.