Rembrandt is widely considered to be the greatest of all etchers. His contribution to the art was fundamental to its transformation into a medium of great vigour and expression. Early in his career, he worked in etching alone. Later he combined it with other techniques, and especially drypoint. The radical changes that he made to his printed designs can be observed through the many successive states and great variety of impressions. For a detailed examination of Rembrandt's etchings, see Felice Stampfle and Eleanor A Sayle, 'Rembrandt van Rijn, 3. Etchings', in Turner, The Dictionary of Art, vol. 26, pp. 172-4. For Ruskin 's most extensive appreciation, see 'Rembrandt, and Strong Waters', in The Cestus of Aglaia (1865-66) ( Works, 19.107-19).