 One of the most persistent criticisms of the National Gallery , apart from those who criticise inadequacies of the building , has been of its conservation policy . The Gallery 's detractors accused it of having had an over @-@ zealous approach to restoration . The first cleaning operation at the National Gallery began in 1844 after Eastlake 's appointment as Keeper , and was the subject of attacks in the press after the first three paintings to receive the treatment – a Rubens , a <unk> and a Velázquez – were unveiled to the public in 1846 . The Gallery 's most virulent critic was J. Morris Moore , who wrote a series of letters to The Times under the pseudonym " <unk> " savaging the institution 's cleanings . While an 1853 Parliamentary Select Committee set up to investigate the matter cleared the Gallery of any wrongdoing , criticism of its methods has been erupting sporadically ever since from some in the art establishment . 
