Marsden — Temperature and Rainfall and Spread of Diseases. 47 



Kewsholme^ has shown pretty conclusively that ''diphtheria only 

 becomes epidemic in years in which the rainfall is deficient, and 

 the epidemics are on the largest scale when three or more years of 

 deficient rainfall immediately follow each other." 



Dr. Gresswell has suggested" that not only the rainfall of the year, 

 but also that for prior years, has influence on scarlatina; and Dr. 

 Longstaff showed^ that the increases in the death-rates from scarlatina, 

 erysipelas, puerperal fever, and rheumatism, in England and Wales, 

 occurred in years of deficient rainfall. 



In the following table I have put down the total amount of rain- 

 fall, the excess of temperature above the normal, and the number of 

 cases of scarlatina, measles, typhoid fever, and diphtheria, occurring 

 in the County Borough of Birkenhead during the years 1890 to 1905, 

 inclusive : — 







Total 



Excess of 

 Tempera- 



No. of 



Number of cases notified during year. 



No. 



Year. 



Rainfall 



ture 



Wet 











in 



in °F 



Days 















Inches. 



over 

 normal. 



in Year. 



Scarlatina 



Measles 



Typhoid 

 Fever 



Diphtheria 



1 



1890 



26-820 



- 0-3 



199 



247 



1620 



182 



35 



2 



1891 



31-643 



- 0-9 



194 



180 



524 



197 



28 



3 



1892 



33-032 



- 1-5 



211 



218 



1542 



150 



25 



4 



1893 



24-537 



+ 1-9 



181 



421 



540 



221 



77 



5 



1894 



27-912 



+ 0-8 



202 



379 



1818 



194 



133 



6 



1895 



26-265 



- 0-8 



172 



430 



258 



192 



142 



7 



1896 



26-633 



+ 1-2 



196 



606 



2166 



149 



115 



8 



1897 



28-580 



+ 0-4 



189 



630 



1141 



152 



80 



9 



1898 



25-719 



+ 1-3 



183 



643 



589 



243 



190 



10 



1899 



27-807 



+ 0-6 



186 



205 



2461 



275 



86 



11 



1900 



32-054 



+ 0-4 



208 



203 



316 



163 



48 



12 



1901 



25-192 



- 0-1 



190 



266 



2179 



207 



75 



13 



1902 



25-566 



- 0-9 



200 



407 



1356 



327 



114 



U 



1903 



34-418 



- 0-1 



224 



658 



420 



79 



101 



15 



1904 



25-175 



- 0-2 



196 



627 



2212 



103 



97 



16 



1905 



24-011 



- 0-1 



192 



874 



979 



63 



138 



Average rainfall for thirty-nine years = 28-613 inches. 

 Average temperature for thirty-nine years = 49-1 ° F. 



The population of the Borough had increased from 98,143 at midsummer, 1890, 

 to 115,979 at midsummer, 1905. This must be allowed for to a certain extent in 

 comparing the number of cases of infectious diseases notified. 



^ Epidemic Diphtheria. (Swan Sonnenschein & Co., 1900.) 



2 A Contribution to the Natural History of Scarlatina. (Clarendon Press, 

 1890.) 



3 Studies in Statistics. (Stanford, 1891.) 



