304 MR. J. BAXENDELL ON CHANGES IN THE SEASONS 



the differences, with one unimportant exception, have all 

 the sign plus ; while during the remaining six years they 

 have all the sign minus. The average value of the differ- 

 ences in the first eight years was 4-3*84, and in the last six 

 years —5*08 inches. The returns from the other stations 

 of the Manchester Corporation Water-works exhibit similar 

 results. It is evident, therefore, that at the end of 1862 a 

 marked change took place in the character of the climate 

 of this locality, the spring and summer seasons becoming 

 much drier, and the autumn and winter months wetter, 

 than they had been during the previous eight years. I 

 may add that this altered character of the seasons was 

 continued through the last year, 1869, the total rainfall 

 at Arnfield during the spring and summer months having 

 been only I2'48 inches against 27-57 inches in the autumn 

 and winter months, thus showing a difference of — 15'09 

 inches. 



In considering the differences in the temperature, humi- 

 dity, and pressure of the atmosphere, and in the direction 

 and force of the wind, in the two periods, as indicated by 

 this marked difference in the distribution of rainfall, it 

 seemed to me highly probable that corresponding differ- 

 ences would exist in the state of the public health, and 

 that the mean rate of mortality during one period would be 

 sensibly different from that during the other. I therefore 

 extracted from the annual Reports of the Registrar General 

 the rates of mortality in Lancashire, Cheshire, and the 

 West Riding of Yorkshire during the years included in 

 the two periods, omitting the last year of the series, 1868, 

 as the Report for that year has not yet been published. 

 These rates are as follows : — 



