Ruskin 's praise of Giorgione is not matched by any very detailed examination of pictures by Giorgione, even of pictures Ruskin considered to be by Giorgione. The Tempest, which is now seen as one of Giorgione's most representative works appears simply as 'one or two Giorgiones' in the Manfrini Palace in Venice ( Works, 11.391), and there is a passing reference to the Dresden Venus in a letter of 1859 ( Works, 7.lii). The Castelfranco Madonna, which Ruskin does consider in some detail, he knew only as an engraving ( Works, 11.240, and see Works, 33.503 where it is referred to as one of the two best pictures in the world). Other paintings mentioned by Ruskin are the Holy Family in the Louvre, which was questioned by Waagen in 1837, and is now generally attributed to Sebastiano del Piombo, a follower of Giorgione, and the Concert Champêtre also in the Louvre and now generally agreed to be Titian 's work.