Margaret De Courcy Lewthwaite Dewar ( 1878 - 1959 ) was a painter. Margaret De Courcy Lewthwaite Dewar s works have been put up for auction numerous times, with realized prices surpassing estimated prices, varying from 168.4 USD for THE CHAPEL AT MAYERNE DE SIRON in 2006 to 980.19 USD for THE LADY SAT ON HER CASTLE WALL WA'BEHELD BAITH DALE AND DOON in 2007 , based on the size and medium of the