[Illustration: CHARLES-FRANÇOIS DAUBIGNY. MOONLIGHT ON THE BANKS OF THE OISE Size of the original etching, 4⅜ × 6½ inches In the Museum of Fine Arts, Boston] Daubigny’s success as a painter, the constantly increasing demand for his work, left him little time, as years went by, for etching. “If only I could paint a picture that _wouldn’t_ sell,” he once said in sheer desperation, and, momentarily, his superb renderings of the mystery of evening and night accomplished his object, though now they are jealously guarded in some of the world’s finest collections. But to _etch_ night, to _suggest_ moonlight--there was a problem indeed! Whistler in his “Nocturnes” paints, so to speak, on his plate with printer’s ink. Daubigny relies on lines alone, to produce his result. “_Night cannot be etched_” is the dictum of more than one authority. No, nor sunlight either, nor clouds! None of these things can be pictured so that blind eyes can see them. But to those who will meet the etcher half way, who are content with a suggestion and are capable of reconstructing from it the artist’s mood, these simple linear plates of Daubigny’s last period are a revelation and a delight. _Moonlight on the Banks of the Oise_ measures scant four by six inches, yet what a feeling of space there is in it! Only a born etcher could have succeeded by means so simple, and seemingly inadequate, in capturing the very spirit of such a scene. Corot’s etched work comprises fourteen plates. It was not until 1845, when he was in his fiftieth year, that he made his first experiment. “Corot took a prepared copper-plate and drew in the outlines and masses of the well-known _Souvenir of Tuscany_, but did not proceed to the ‘biting in’ process. Some years later Félix Bracquemond discovered the plate in a nail-box at Corot’s studio and begged the master to complete it, offering to take charge of the ‘biting in.’ Corot then took the plate and added the tones and details of the final state.... There was something in the use of mordants and acids that seemed to frighten Corot, and he always called in some good friend such as Bracquemond, Michelin or Delaunay to assist in this delicate process.”[15] [15] Le Père Corot. By Robert J. Wickenden. The Print-Collector’s Quarterly. Vol. 2, No. 3. p. 382.