Rotary drum digger, Victoria Line

This photo shows tunnelling on last section of the Victoria line at Kings Cross. The crew are resting at the cutting face of their rotary drum digger. The northern sections of the line were built using this digger, which was a new type of tunnelling machine. A maximum tunnelling speed of 120 metres a week was achieved in the trial tunnel, which seemed reasonable for the new line. New forms of tunnel lining using both concrete and a flexible-jointed cast-iron segment were also tested. Contemporary reports suggested that shortages of skilled and semi-skilled labour were one of the most difficult problems affecting the project.