Christian missionaries in medicine and education have contributed greatly to African advancement - many outstanding African leaders are the products of mission schools - but they have also been blamed for some of the worst ravages of western imperialism on the continent. Africa Calling, based on the letters and contemporary records of Herbert (Bert) Gerrard and his wife Doris, leaves readers to balance these claims for themselves while showing the practice of medicine in the most difficult conditions. On the 'hut call' and in the mission hospitals he dealt with a huge range of medical problems from gastro-enteritis, measles - a deadly disease in Africa - pneumonia, malaria, leprosy - the whole range of tropical diseases.