[8][9] Together with the earlier bequest of David Scott Mitchell the printed book collections represent the published history of Australia and especially New South Wales of the time.

Also included are significant collections relating to Australian literature, theatre, art, architecture, sport, natural history, Indigenous material and biography.

[10] "Dixson's collecting soon widened to include many formats – not only books and manuscripts but pictures, coins, medals, curios, relics, postage stamps, bookplates and maps.

[11] At first the collection was for his own use but "...when he learned that the income from David Scott Mitchell's bequest to the Public Library of New South Wales could not be spent on pictures, he 'decided to give special attention to them'".

Many of the maps are rare manuscript copies by inland explorers including Sir Thomas Mitchell, Ludwig Leichhardt and Augustus Gregory.

He also provided funds to establish the Sir William Dixson Foundation, which aimed to make rare materials on Australia and the Pacific available to students, through the production of facsimiles.