BOOK REVIEW / Mrs Wheeler and her astringent Solomon: 'Letters from Margaret' - Ed. Rebecca Swift: Chatto, 13.99 pounds

'YOU cannot afford to buy books. Neither can I. Nobody can nowadays, when a serious book costs from 18 to 25 shillings. If you spend the money they cost on drink, you will be better company at home and elsewhere.'

George Bernard Shaw offered this advice to Margaret Wheeler in October 1948, when she was 40 and he 91. She didn't take it, and her next letter to him begins: 'Dear Old Astringent, Garn] You've only got hold of half the story.' Offering, and not taking, advice is the real meat of their correspondence, which must have done a lot to enliven the last seven years of Shaw's life. It also helped Margaret to come to terms with a strange and knotty problem.

In 1936 Margaret Wheeler and Blanche Rylatt gave birth to girls on the same day in the same nursing-home. The children were inadvertently given to the wrong mothers, but only Margaret was sure of that. Having done all she could to 'constrain, compel, badger, pester and frighten' the Rylatts into admitting even the possibility of the swap, and

having failed, she became desperate.

She hit on the idea of enlisting the help of Shaw because, as she told him, 'common people everywhere regard you with astonishment, admiration and respect, so that you are in some danger of being instituted the Eighth Wonder of the World'. Cleverly, she aroused his interest by inventing a new phonetic alphabet, which was a project he had famously cherished. Once he was hooked, she told her latter-day Solomon all about her dilemma.

Shaw tackled it with relish, suggesting various courses and radical solutions, but there really was no easy answer and after a time they began to write about other things. Shaw was widowed and lonely, Margaret's husband was away at the war and a strange flirtatiousness began. Shaw asked her for her photograph and wrote immediately he received it: 'As I guessed, a joyous creature, a charmer . . .' He sent her his, describing himself as 'trying desperately to look as young as possible'. She considered it smashing.

It is fun to read this teasing. Shaw says: 'I can't write. I'm too old.' Margaret replies: 'Stuff and nonsense.' Shaw offers his opinion that children should be allowed to be as noisy and messy as they like. Margaret, always clearing up after her four, responds: 'Mr Shaw, how could you?'

He tells her Beatrice Webb reckoned housework took only half an hour a day, but backs down under Margaret's detailed, enraged response, admitting that the Webbs had two servants and a thousand a year and that Beatrice was remarkably incompetent: 'If she had tried to do housework, she would have wrecked the building.'

They discuss war, birth control, corporal punishment, writing and the role of women - particularly the last. Shaw declares that all public bodies should consist of men and women, 50:50, adding that women 'make so much better monarchs than men that there ought to be an anti-Salic law to exclude men from the throne'. Margaret applauds the sentiments, but bemoans the eternal drudgery of female domestic routine.

In his penultimate letter to her, Shaw gives this response: 'Certainly it would seem that the repetition of the same chores day after day all one's life must be unbearable. I once asked a Miss Perigall, aged 102, what it was like to be a centenarian. She replied: 'Nothing but buttoning and unbuttoning'. The only way to get rid of housework and mothering is simply not to do it.'

Shaw admired and encouraged Margaret's vivid style of writing. She clearly drew great support from his enthusiasm. 'I never before advised anyone to take up literature as a profession,' he writes. 'Do not let me down.' Her reply is vigorous: she points out the hideous responsibility of such an admonition, then adds: 'Blimey. You are a dreadful man. I can't think why I'm so fond of you.' After his death she took up pottery, not literature, and made a small but successful career for herself in Cumbria, where she still lives.

And the babies who had started all this? They were eventually told of their true identities, accepted each other's families as extensions of their own, and seemed none the worse for their transplanted childhoods.