⁹Ireland, Aideen M. Roger Chambers Walker: A Sligo Antiquarian. The Journal of Irish Archaeology 11 (2002): 156.
Some of the Walker/Nothumberland objects in the National Museum of Ireland were purchased by the State from Sotheby's London in December 1990, from the trustees of the will of the 10th Duke of Northumberland. The Walker collection was originally purchased for Alnwick Castle by Algernon Percy, 4th Duke of Northumberland, who in 1852 was named First Lord of the Admiralty.
Aideen Ireland quotes from an editorial in The Dublin Saturday Magazine highly critical of the deceased antiquarian: "The late R .C. Walker who, in search of antiquities, had opened more ancient tombs than any other person of modem times in this country, possessed an almost unique museum of Pagan and early Christian works of art and art manufacture, relics of the various races which had ruled in Ireland from pre-historic times. His entire collection was sold by his executor to the late Duke of Northumberland. Where is it now? And yet Mr Walker received, as presents from friends, very many of his best specimens on the clear understanding that he collected only for national and patriotic purposes, and that no portion of the contents of his museum, should ever be allowed to leave Ireland. Many other instances of the wholesale exportation of Irish antiquities might be referred to; and we regret to say that a regular traffic in such articles with English curiosity-seekers is to this day carried on by well-to-do and even professional men who would scorn to be styled tradesmen, but who act like peddlers in their greediness for a miserable profit, and like rogues, in procuring antiquities from patriotic sellers at a cheap rate, under the pretence that they are gentlemen, who only collect such matters through love for fatherland." (The Dublin Saturday Magazine ii, no. 43, [1865-7], 250.)