A poet's amble in prose through poetry and other byways of language and art. Wilbur, who published a previous volume of prose pieces, Responses, in 1976, calls this sequel ``a mixture or jumble of efforts in various . . . modes.'' But it is more and better than that. He magnetizes subjects of literary and personal interest (e.g., Edgar Allen Poe; the craft of translation) that combine eventually to suggest an intellectual self-portrait. For example, consider his opinionated yet revealing comment on cinema in ``Movies and Dreams'': ``Watching film is (for me, for most) so much less judicial and analytic than other art experiences. The conventions are transparent, the molding of the imagination is insidious.'' Although basically conservative and somewhat patrician in taste, Wilbur can turn this tendency into a means of stimulation with his precision of mind and language--even if you happen to disagree with him. In one essay, for instance, he does his best to raise the standing of often-derided poet and patron Witter Bynner. He is alert and fair, announcing in ``Forewords'': ``I hope that a persistence or resurgence of metrical writing, and of artifice in general, will now restore some lost force and expressive capability in American poetry.'' Nevertheless, he also recognizes that ``no form belongs inevitably with any theme or attitude; no form is good or appropriate in itself, but any form can be made good by able hands.'' The book includes surprises, notably Wilbur's lecture about riddles, given in 1988 at the Library of Congress. Here he surveys types and scrutinizes examples of riddles with a playful earnestness, arguing in favor of their acceptance as ``a poetic form.'' Wilbur's clarity and his rationalness--his lack of romantic sympathies--will strengthen his appeal for some. A smart, cleanly written, yet not especially adventurous harvest.