The Inklings and King Arthur includes Suzanne Bray's "'Any Chalice of Consecrated Wine': The Significance of the Holy Grail in Charles Williams's War in Heaven." As I begin it, I appreciate its freedom from academic cant and verbosity.
However, I'm wondering about her statement that Charles Williams was personally acquainted with Arthur Machen. I'll look into this some more, but I can report that there is no index reference to Machen in Grevel Lindop's recent biography of CW nor in Alice Mary Hadfield's two earlier books on Williams.
I'm puzzled by Dr. Bray's reference to Machen's The Secret Glory as being Machen's "best-known work"! Machen is much better known, I'm sure, for "The Great God Pan," "The Black Seal," and "The White People," repeatedly anthologized horror stories. The Secret Glory is the second of Machen's three novels, with The Hill of Dreams, his first and best-known, and The Green Round, his third, and my own personal favorite of the three by a long throw.
I don't much like The Secret Glory, by the way. I recall it as indulging far too much in self-pity and self-pleasing fantasy. In the 1920s, Machen's publisher released Precious Balms, a collection of negative reviews of Machen's works (yes, that's right).
Punch revealed that the Secret Glory is that of the Holy Grail, “revealed in a Welsh farmhouse to the boy Ambrose Meyrick and his father.” The mystically-initiated boy “is sent to an exquisitely odious public school, where he becomes first a cowed and isolated dreamer and last a furtive and malicious rebel.” Ambrose runs off with “a sympathetic parlour-maid” after Machen has gratified his “savage humour” against the public school system. Unfortunately Machen never really comes to grips with the targets he satirizes. The Evening Standard found the book “incoherent and tiresome” since schoolboys and mysticism “do not mix.”
The Manchester Guardian mentioned the “escapade” in which Ambrose goes to London with the “young lady of his choice,” detecting in the treatment a quality of “inebriate innocence.” Rose Macaulay in The Daily News said that while Ambrose’s mystical experiences are described “with a good deal of beauty,” Machen’s attempts at reporting his hero’s “contacts with actuality” are “distorted and unreal”; there was “a good deal of silliness” and “bad taste” in the book.
--It's believable, though, that Williams and Machen had a common acquaintance in Evelyn Underhill, author of Mysticism, etc. She dedicated her weird novel The Column of Dust (which I found unreadable) to Machen, while Williams edited a selection of her letters. Well, maybe Williams and Machen knew each other, but I'm not yet convinced that they did.