"What for practical purposes may be regarded as an experiment of the same kind is being conducted in West Africa. Dr. Elliot, a member of the Liverpool expedition sent to Nigeria some time ago to investigate the subject of malarial fever, has recently returned to this country. He reports that the members of the expedition have been perfectly well, although they have spent four months in some of the most malarious spots. They lived practically amongst marshes and other places hitherto supposed to be the most deadly. They have not kept the fever off by the use of quinine, and they attribute their immunity to the careful use of mosquito-nets at night." (_British Medical Journal_, 22nd September 1900.) [38] Sir Patrick Manson, in the _British Medical Journal_, 29th September 1900, gives the following account of this experiment:--"A wooden hut, constructed in England, was shipped to Italy and erected in the Roman Campagna, at a spot ascertained by Dr. L. Sambon, after careful inquiry, to be intensely malarial, where the permanent inhabitants all suffer from malarial cachexia, and where the field-labourers, who come from healthy parts of Italy to reap the harvest, after a short time all contract fever. This fever-haunted spot is in the King of Italy's hunting-ground near Ostia, at the mouth of the Tiber. It is waterlogged and jungly, and teems with insect life. The only protection employed against mosquito-bite and fever by the experimenters who occupied this hut was mosquito-netting, wire screens in doors and windows, and, by way of extra precaution, mosquito-nets round their beds. Not a grain of quinine was taken. They go about the country quite freely--always, of course, with an eye on _Anopheles_--during the day, but are careful to be indoors from sunset to sunrise. Up to 21st September, the date of Dr. Sambon's last letter to me, the experimenters and their servants had enjoyed perfect health, in marked contrast to their neighbours, who were all of them either ill with fever, or had suffered malarial attacks."