This book assesses Ruskin’s and Turner’s mutual interest in the theme of water, with particular reference to The Harbours of England (1856), Ruskin’s book on ships and marine art to which are appended Turner’s 12 illustrations of the English ports. By considering existing scholarly works on Ruskin and Turner, the book begins by demonstrating that the two, despite their widely acknowledged relations, have rarely been examined in conjunction. It raises the question as to how the subject of water inspired the intellectual, aesthetic, philosophical, and scientific climate of the nineteenth century, both in Britain and abroad, and acknowledges the significance of the relationship between Ruskin and Turner in the context of aquatic studies. Ruskin’s childhood fascination with water is examined in detail, while the scientific and spiritual importance of the subject in Modern Painters and The Stones of Venice is also emphasised and read in parallel with The Harbours of England, a detailed account of which is given, referring to both text and illustrations. Turner’s role in Ruskin’s understanding of specific water-pictures is also reconstructed. The book demonstrates that water is important as a multifaceted compendium of contemporary themes, for tradition, progress, nationalism, and patriotism find their iconography in its depiction. Considering the literary and painterly implications of wateriness, the text concludes with a reflection upon the significance of the study of water for Ruskin and Turner, and for their age.