Turner used this sketchbook intensively for the first half of his 1817 tour, both at the Field of Waterloo and along the Rhine. All the sketches on ff.71v-72r belong to his return journey from Mainz to Cologne in late August. The elongated sketches extending across the top of the two pages were drawn from a boat bearing Turner downstream from the widest part of the Middle Rhine towards the Bingen gorge where the river becomes enclosed by steep hills. The last of these sketches later formed the basis of no.11. The final sketch shows the pilgrimage church at Bornhofen beneath the rocky ridge occupied by the two castles known as 'The Brothers'.