8vo. 20pp. With a tipped-in errata slip. Sewn as issused, in original publisher's printed tan wrappers. Extremities sunned and a trifle spotted. Internally clean and crisp. Presentation copy, ink inscription to head of upper wrapper: 'With Sir Ronald's Compliments'.

The first edition of a reproduction of three letters on the transmission of malaria between eminent malariologist Sir Ronald Ross (1857-1932) and his mentor, physician and parasitologist and pioneer of tropical medicine, Sir Patrick Manson (1844-1922). In 1902, Ross was awarded the Nobel prize for medicine or physiology for his research into the propagation of the disease via mosquitoes.