The Valencia Chalice

SIR,--As the author of a forthcoming book about Glastonbury I was much interested to read Fr. McCormack's article on the Valencia Chalice. It raises a crucial issue. One of the mysteries of the Grail is that, despite the obvious importance of this relic, nobody apparently claimed to possess it or to know anything of its history till after the appearance of the Arthurian stories which were not " Holy Relic" legends in the ordinary sense, and were never countenanced by the Church. The Valencian Chalice, I had supposed, was no exception, since it was not publicised till the fourteenth century or later.
But Fr. McCormack mentions a document of 1134, i.e. well before the Arthurian writers, and says St. Joan de la Pano was the original Grail Castle. I doubt if he fully realises bow this theory would
transform Arthurian studies ! Could he give a few details to establish the authenticity of the document, and offer his suggestions as to why none of this story was given slut openly till so long afterwards?
Geoffrey Aahe 213 Queen's Road, Maidstone, Kent.