Madame Moitessier, 1856 by Jacques-Auguste-Dominque Ingres, National Gallery of Art, London.
True to the fashion of his time, Ingres was more interested in painting historic scenes than doing portraits, but also true, portraits are an artist's bread and butter. Mme. Moitessier's husband asked Ingres to paint his wife's portrait and Ingres refused, upon meeting her however, he was intrigued and agreed to paint her. Notice how the use of the mirror behind her, gives us two portraits in one.
One of the most important British painters of the 19th century, Constable believed in painting out of doors in order to capture the most true, and realistic atmospheres, for his paintings. He did studies of nothing but clouds, so that he could render them perfectly. This is his most famous work featuring a hay cart, or hay wain, being ferried across the River Stour. The house in the background still exists and is in the care of the National Trust.