This drawing by the Swiss artist Abraham-Louis-Alphonse Ducros — a preliminary sketch with a deep perspectival view of the Arch of Titus in Rome, and inspired by Panini’s Arch of Titus, 1745 — is the basis for one of his standard images, a definitive view of Rome sold to eighteenth-century tourists who wanted to furnish their houses with images of the Grand Tour. It is exemplary of the kind of observations done for a mass market of tourism and using a low, vertical composition that emphasises the monumentality of the arch. Ducros is experimenting with these produced views of Rome. He was renowned in the late eighteenth and early nineteenth century, regarded by artists and collectors alike as one of the most important figures of observations in watercolour.