Why does Silas decide to visit Lantern Yard? What changes have occurred in Lantern Yard over the years?

Silas wanted to visit Lantern Yard because he wanted to revisit the past after time had healed his wounds. However, there was no Lantern Yard left. There was a house with overhanging windows in its place. He could not learn anything about his old friends either, the old place had been pulled down, his old home was gone, it was as if his past had vanished.