"[Turner’s work was] a grey picture, beautiful but true, but with no positive colour in any part of it. Constable’s ‘Waterloo’ seemed as if painted with liquid gold and silver, and Turner came several times into the room while [Constable] was heightening with vermilion and lake the decorations and flags of the city barges. Turner stood behind him looking from the ‘Waterloo’ to his own picture, and at last brought his palette from the great room where he was touching another picture, and putting a round daub of red lead, somewhat bigger than a shilling, on his grey sea, went away without saying a word. The intensity of the red lead, made more vivid by the coolness of his picture, caused even the vermilion and lake of Constable to look weak. [C.R. Leslie] came into the room just as Turner left. ‘He has been here,’ Constable said, ‘and fired a gun.’ . . . The great man did not come again into the room for a day and a half; and then, in the last moments that were allowed for painting, he glazed the scarlet seal he had put on his picture, and shaped it into a buoy."
John Gage via Earth and other unlikely worlds