One of the most intriguing books I have recently read is Graphic Witness, a collection of four wordless graphic novels edited by George A. Walker. I bought it because I knew and love the work of Frans Masereel, one of the featured artists. I'll have to post about him later. An artist that was new to me is Lynd Ward.
Ward produced a number of wordless graphic novels, made up of a series of striking woodcuts in a sort of Expressionistic/Gothic/Art Deco style. Three of these have been recently republished in attractive, easily affordable editions by Dover, while another, Vertigo, seems to be out of print. A fifth, Song Without Words, I could not find a cover for.
Ward is probably best known, at least in his native US, for The Silver Pony, a children's book he wrote and illustrated.
He also did the covers (and illustrations) for a number of other children's books.
In addition, he has done covers and interior illustrations for a number of classic novels as well. The cover one without a title below is Richard Hughes' A High Wind in Jamaica. Of the Frankenstein, more to follow...
I found a couple of other books with his work on the covers.
Here are some of the marvellous interior illustrations for Mary Shelley's Frankenstein.
Here are some of the pages from Gods' Man...
..from Mad Man's Drum...
..and from Song Without Words.
And here's an illustration for an edition of Beowulf that I can't trace.
Much more Ward can be found here, here and here (the last of which leads you to all of the Frankenstein illustrations--beware, though, that it also belongs to a mildly mad chap determined to prove that Percy Shelley wrote Frankenstein, rather than it being the work of Mary Shelley).
UPDATE: Will of A Journey Round My Skull has got his hands on a copy of the Beowulf (see comments), and has reproduced the beautiful artwork from it here. Go and look and marvel!