AND THE RATE OF MORTALITY. 307 



eight yearSj 1847-54, in which the spring and summer 

 rainfall was considerably below that of autumn and winter, 

 the average rate of mortality in Lancashire was 2*87 1, and 

 that in the next following eight years, 1855-62, in which 

 the rainfall of spring and summer was considerably above 

 that of autumn and winter, the rate of mortality fell to 

 2-558, but that during the five following years, 1863-67, 

 when the spring and summer rainfall again fell decidedly 

 below that of autumn and winter, the mean rate of mortality 

 rose to 2'775 in spite of all the sanitary improvements 

 that had been made in almost every town and district in 

 the county. Looking to the enormous sums of money 

 that have been expended of late years, by boards of health 

 and town councils, in making sanitary improvements, these 

 results show clearly that the efiects of meteorological 

 changes upon the public health far exceed those arising 

 from defective drainage, ill-contrived privies and water- 

 closets, crowded dwellings, and an insufficient supply of 

 good water, and that no material and permanent reduc- 

 tion in the rate of mortality can reasonably be hoped for 

 until a close and careful study of the influence of changes 

 in the state of the atmosphere upon the production and 

 development of disease has led to the discovery of the 

 best means of guarding against and counteracting the 

 effects of unfavourable changes of the weather, and the 

 people have been induced to avail themselves of such means 

 to ward off or mitigate attacks of disease. 



In the Reports of the Registrar General the causes of 

 death are divided into five classes : — 



I. Zymotic. 

 II. Constitutional. 



III. Local. 



IV. Developmental. 

 V. Violent deaths. 



x2 



