aiarterly Journal ,of S ci eric e , N c 



63 HEALTHY DISTRICTS OF ENGLAND 



20to4() 



To-8tr- 



DURHAM AND NORTHUMBERLAND DISTRICTS 



STAFFORDSHIRE DISTRICTS 



30 



td40 



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MERTHYR TYDFIL. 



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D R FARRS DIAGRAMS OF THE PROPORTIONAL NUMBERS OF MINERS, 

 LIVING- AT 4- PERIODS OF LIFE, IN 4- MINING DISTRICTS , COMPARED 

 WITH 63 HEALTHY DISTPJCTS. 



