sentences:  Major earthworks were required to build ramps to link the tunnel's Northland Road, Raroa Road now Crescent and Karori Road now known as Chaytor Street at a gradient suitable for trams.Tunnelling found greasy and treacherous ground requiring double shifts on the tunnelling to complete lining and stabilising as quickly as possible.In view of the public's unease for the safety of the workmen an expert tunneller, a Mr Robert Semple, was called in to inspect the site.