Points A and B on Hooke’s drawing—the places in the sheer bank of Fleet Ditch where it connected to the moat—were clearly identifiable, but they had been sealed by a pastiche of iron grille-work and masonry with gaps between bricks to let stuff flow through. Saturn with a skiff and a powder-keg could have made short work of these, but it would have been rather noticeable, there in the midst of the city, all of a quarter-mile from St. Paul’s Churchyard.