Construction of a sewer from Belgrave Square to Barking, under London, in 1910. On the right of the image is the 'Greathead Shield', which was pushed through the clay soil by compressed air. The centre of the image shows two men working on the lining of the new sewer, constructing the iron frame of the sewer and then facing it with concrete and bricks. On the left of the image is the completed sewer. This work was being undertaken by Mowlem, at a cost of ?375,000.