What happens when two of the best-known writers of the day take on subjects that have been exhaustively written about by others? Listen to decide whether they are giants on the shoulders of dwarfs, or vice versa.

Reading his own brief study Shakespeare, Bill Bryson jogs along in his own ineffable way, good-humoured, undoctrinaire, nodding respectfully at experts but confidently following his own inclinations in what he selects from the mountain of myth that surrounds the Bard of Avon – the molehill of fact is quickly dealt with.

He tells us about eccentric early experts and the disagreements of modern ones, and of his own explorations in the National Archive. He describes the legendary first folio, the collection put together by admiring contemporaries that ensured Shakespeare’s enduring fame and disposes briskly of the Francis Bacon-as-author theory.

He is shrewd on telling detail – Will’s family enters the frame, a wheeler-dealer father who was frequently chased by the law, a younger brother, Ed, who was also a keen actor, a son named Hamnet, who died young.

There is a plausible explanation of how Will first got to London and vivid pictures of life there – outbreaks of plague every ten years, an uncertain religious and political climate. When the book closes with a survey of changing estimates of Shakespeare over the centuries, we feel that we know all that we need to.

Peter Ackroyd has a much harder task in Thames: Sacred River. A biography can begin with a birth and end with a death. The Thames is a subject with no boundaries: its origins, as Ackroyd describes with eloquence, lie back in prehistory, before a channel divided Britain from continental Europe; it and its many tributaries can never really be said to end.

To deal with such “liquid history”, Ackroyd takes the frame of the river’s symbolic and sacred associations – baptisms and committals, worship and punishment, lawmaking and rituals of cleansing; its influence on writers, musicians and artists.

You won’t agree with all his claims, but I enjoy shouting back at an audiobook, especially as the narrator, Simon Callow, spouts out the cascade of facts with such overwheening certainty. It has been abridged by Kati Nicolls, who is to be congratulated on keeping the music of Ackroyd’s prose and filletting the text all but invisibly.

Buy Shakespeare by Bill Bryson
Harper Collins, unabridged, 5 CDs, £13.99

Buy Thames: Sacred River by Peter Ackroyd
Random House, abridged, three sets of 3 CDs, £13.99 each

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