After seeing these Pre-Raphaelite landscapes, let us imagine ourselves straightway turning to one of the numerous scenes by Whistler of the Thames at twilight, with its glimmering lights and ghostly shapes of bridges and hulks of steamers. Nothing is outlined, nothing is clearly defined, but the mystery of London's river is caught and pictured for ever. Let us look, too, at his 'Valparaiso,' bathed in a brilliant South American sunshine, where all is pearly and radiant with southern light. Even here the impression is not given by the power of the sun revealing every detail. There are few touches, but like Velasquez, he has made every touch tell. As the Pre-Raphaelite Brotherhood kindled their inspiration by the vision of the fifteenth-century painters of Italy, so Whistler and many other modern artists have turned to Velasquez for guidance. Till the last half of the last century his name had been almost forgotten outside Spain. Now, among the modern 'impressionists' so-called, he is perhaps more studied than any other painter. When we were looking at the pictures of this great man, we saw how he and Rembrandt were among the earliest to learn the value of subordinating detail in the parts to the better general effect of the whole, so as to present no more than the eye could grasp in a comprehensive glance. Every tree and stick in Brett's 'Val d'Aosta' is truthfully painted, but the picture as a whole does not give the spectator the impression of truth, for the simple reason that the eye can never see at once what Brett has tried to make it see. All the wonderfully veracious detail in the work of the Pre-Raphaelite does not give the impression of life. Men like Holman Hunt, on the one hand, and on the other hand Whistler, living and working at the same time, exhibiting their works in the same galleries, differ even more in their ideals than Velasquez differed from the fifteenth-century painters of Italy. Facts such as these make the study of modern art difficult. Before the nineteenth century, pictures of the same date in the same country were painted in approximately the same style. But during the last fifty years many styles have reigned together. At one and the same time painters have been inspired by the Greek and Roman sculptors, by Botticelli, Mantegna, Titian, Tintoret, Velasquez, Rembrandt, Reynolds, and Turner, and the work of each is, notwithstanding, unmistakably nineteenth century, and could never have been produced at any other date. Every artist finds a problem of his own to solve, and attacks it in his own way. When Whistler painted a portrait he endeavoured to express character in the general aspect of the figure, rather than in the face. The picture of his mother is a wonderful expression of the sweetness and peace of old age, given by the severe lines of her black dress and the simplicity and nobility of her pose.