INTRODUCTION 
The Liverpool School of Tropical Medicine despatched the 
fifteenth expedition comprising Dr. Anton Breinl and the writer to 
Manaos in April, 1905, in order to investigate yellow fever and the 
diseases of the Amazon State. This expedition was the second sent to 
the Amazon region, the first one in 1900 having been stationed in Para. 
Shortly after its arrival in Manaos, both members were attacked by 
yellow fever, and subsequent complications in the case of Dr. Breinl 
unfortunately necessitated his return to Europe, and thus his 
valuable services were lost to the expedition. 
No trained assistance was procurable and all the work has had 
to be performed single-handed. The report presented embraces 
only a portion of the work of the research laboratory in Manaos. I 
have to thank those gentlemen who were kind enough to contribute 
chapters to this report ; it would have been impossible otherwise to 
have dealt with such a variety of subjects. It is hoped to complete 
later the account of all the investigations pursued during the years 
1905 to 1909, and to publish, at short intervals, a series of papers on 
subjects affecting the welfare and hygienic conditions of the Amazon 
region. The district is so rich in material that it would require a 
large staff of workers to carry out the researches on the spot; by 
collecting the material and forwarding it to Europe, it is possible to 
induce European authorities to issue short monographs on their 
subjects. 
In many respects the 1905-1909 Expedition to the Amazon 
differs from the expeditions previously despatched by the School. A 
permanent laboratory was necessaiy, and attention had to be given 
to a multiplicity of details which are usually foreign to a travelling 
commission. On the other hand numerous advantages arose out of 
the permanency of the laboratory, since patients could be kept under 
continued observation and experiments inaugurated which would 
have been impossible under other conditions. 
The main object of the expedition was to investigate yellow 
fever, and, if possible, endeavour to advance our knowledge of this 
disease. Chimpanzees have been successfully inoculated , rabbits 
and guinea-pigs have exhibited certain reactions when inoculated 
