Blow The Wind Southerly: Kay Brownbill

The shadows of William the Sailor and Charles Fallton reach across the decades from the colonial days of Australia to fall on two lovers in modern England as Langdon Bonython unravells the mystery that lies behind the enigmatic letter Peter de Frene receives on the death of his father. A fascinating mystery novel, first published in 1962. https://en.wikipedia.org/wiki/Kay_Brownbill