Most people's hearts betray them at some time or another, but whether they betray an inner truth or necessity by exposing it, or cheat their owners into a false situation, is a matter of fine judgment. Chisholm's heart was undoubtedly restless, and his muse was not of the sort to stroke the fevered brow. They betrayed him doubly. They led him away from a marriage which had in many ways been an excellent and fruitful match, into a new and undoubtedly rejuvenating love and then failed to stand up to the strain, physiologically. Diana also had lost heart and was setting up her own establishment by late June 1961, while Erik was already suggesting the possibility of divorce. He was frequently out in Durbanville (where Sheila was living), having had his own Bechstein piano moved there, and found his time in Cape Town a hell by comparison. In Durbanville, he worked on The Nun's Priest's Tale, sending Sheila out to find a suitable cockerel to bring home so that he could make use of its crowing – the plot of the tale concerns a cock, a hen and a fox (see Chapter 9).

But the award of a sabbatical for 1962 was, perhaps, the final catalyst in the breakup of his marriage.

It was a sadly appropriate time for Chisholm to be studying Burns's loves in particular. Diana, who had been his mainstay and had supported him loyally for so many years, had never quite matched the sexual energies of a man who knew himself he had been born with too much energy.