r,26 SEDGWICK AND WINSLOW. BACILLUS OF TYPHOID FEVER. 
seasonal distribiitlou of tlie more important diseases, and pointed out the contrast be- 
tween such diseases as bronchitis, pneumonia, and croup which culminate in the winter 
and the fevers and diarrhoeal diseases which attain a maximum in the hot months, 
ills curves showed a slight rise in October for typhoid fever and much more marked 
rises for the classes of " Typho-malarial," *^ Remittent," and " Intermittent " fevers, 
the n^iues for which in absolute value greatly exceeded those for the former disease. 
Slinllar tables were published in the succeeding annual reports; and in 1882 it was 
stilted that " more than the average per cent of weekly reports stated the presence 
of typhoid fever in months when the average daily temperature, the average daily 
range of temperature, the absolute humidity of the atmosphere, the monthly and the 
average daily range of the barometer and the average daily pressure of the atmos- 
L 
phere were greater than the average for the year ; and less than the average per cent 
of reports stated the presence of typhoid fever in months when these conditions were 
less I ban the average for the year." These curves and conclusions have been repeated 
year by year in each annual report, the only change being the gradual increase of 
"typhoid fever" relative to the " typho-malarial " and "remittent" fevers with 
itiipiovement in diagnosis. In 1884, Dr. Baker ^"^^ treated typhoid fever in more 
detail, comparing the 
of the disease for five year 
of the ground water in Michigan and showing that the disease increased quite regularly 
with the number of inches of earth above the water in the wells. He concluded that " in 
summer when vegetation is active and not decaying, a lowerirrg of the water is 
uniformly followed by increased prevalence of typhoid fever; with the advent of 
colder weather there is a rise in the water level which is uniformly followed by a 
decreased prevalence of the fever ; that this decrease continues through the winter 
and .spring even though the level of the well water Is lowered, provided the surface 
of the earth is deeply frozen ; that on the contrary high-water level in wells in winter 
and spring coincident with ground not thoroughly frozen is followed by increased 
prevalence of the fever." 
The relation to ground water was again studied in the Report of the Michigan 
Board of Health for 1888 (p. Iv.), and 1890 (p. 247); and in the Report for 
St 
l'^94 (p. 300) and succeeding reports, new diagrams were published and the follow 
conclusions were added ; "The evidence is conclusive that there is a necessary relation 
between the low water in wells and the sickness from typhoid fever. The fluctuations 
in the sickness from typhoid fever and the depth of the water in wells are nearly 
coincident throughout the several months. The maximum of sickness and the 
minimum of water are coincident in October." Finally, in 1897, Dr. Baker ^^-«' 
