In the Royal Academy, pictures were finished on "Vanishing Day". Set up in 1809 in order that artist could have 3 or 4 days in which  to retouch their work. Turner would send in an almost monochrome painting, which did not distract from the neighboring painting. On vanishing day Turner arrives and transform  his paintings with glorious chrome, vermilion etc until they literally blazed with light and colour. The poor artist hang next to him now paled into insignificance. One time this was the great John Constable exhibiting his "Opening of Waterloo Bridge", Turner stood behind Constable watching him  put colour on the flags, next day Turner brings his palette and paint a red boey on the sea then just left...."He has been here' said Constable, 'and fired a gun',

Caricature: Turner painting one of his canvases. Extract from the Almanac of the Month, June 1846. Depicted on Varnishing Day at the Royal Academy. He would send in an incomplete picture, which he would proceed to finish in front of his astonished colleagues. His cloths are not a caricature, he always dressed in this manner. The word yellow painted on the bucket is an allusion to his attachment to this colour. Turner associated yellow with the brightest form of light and joy.

Constable looking at one of Turner’s paintings at the Royal Academy said to Turner “I do not see nature that way.  “Ah” said Turner “do you wish that you could” More on Turner's methods

Extract From Farinton's Diary on how Turner paints

" Light is created by painting over the areas that he wishes to illuminate with a wet brush (a general background has already been applied with a deep colour where necessary) and with some blotting paper heighten the resulting wet colour. After this he recleans the area with pieces of bread. Any other colour could now be applied here. White chalk is now used to heighten the forms which must be illuminated. A rough and full form can be obtained by passing a camel-hair brush over these forms, which reduces the dampness of the area thus touched so that only those areas affected by the blotting paper are heightened."

Turner used extraordinary colours, often applied pure, and never failed to suggest depth, air, and luminous transparency, his painting ultimately, are pure light and colour. The painter of light. Turner learned to paint by copying the work of Alexander Cozen. In Turner's day ultramarine cost around 8 guineas(£8.80) per ounce, while the synthetic (french ultramarine) was less than a £1.