Lane’s successor, Robert Langton Douglas (1864-1951) accepted the directorship, with the permission of the War Office, in 1916. He was a serving Captain in the British Army, having enlisted in 1914 at the age of fifty. A renowned expert in early Italian renaissance art, he was also a successful art dealer. During his tenure, he presided over the Lane and Hone bequests. Amongst his acquisitions is Romano’s The Virgin invoking God to heal the hand of Pope Leo I and Osborne’s Near St. Patrick’s Close, an Old Dublin Street, but limited funds allowed for few purchases during this period. Langton Douglas' frustration at this is apparent in a letter he wrote to Bodkin after attending an auction in 1918, ‘I could have wept with rage … when I saw our rivals, with pockets full of money… bidding as they liked…’
Langton Douglas was the first great champion of the Gallery’s library collection. Against all odds, funding for the library was secured for the first time in 1917 when the Treasury agreed to provide £120 for the purchase of books for the Gallery. The Director believed that the gallery was in need of key art history reference books, and insisted that they were indispensable for the staff and the public for the study and full appreciation of the collection. Langton Douglas made quite a number of purchases for the library during his tenure and is thought to have paid for the cataloguing of the library collection from his own funds.
The part-time Director based himself in London, working at the War Office until 1918, as well as continuing his art dealership. He resigned in 1923.