THE SOIL IN ITS RELATION TO DISEASE. 



A REPORT OF OBSERVATIONS 



BY 



T. E. LEWIS, M.B., AND D. D. CUNNINGHAM, M.B. 



The following Keport embodies the results of observations -which have been carried 

 out with a view of determining to what extent peculiar conditions or changes of 

 condition in the soil in Calcutta affect the prevalence of disease in general, and of 

 certain diseases in particular. 



The phenomena forming the subjects of observation were : — 



(1) The amount of moisture in the soil; 



(2) The temperature of the soil ; and 



(3) The amount of carbonic acid in soil-air. 



As is well known, marked attention has lately been directed to the importance 

 of soil-meteorology as affecting the prevalence of disease, and it formed one of the 

 subjects to which our attention was directed by the Army Sanitary Commission and by 

 Dr. Parkes. Most careful observations have been published by Dr. Max von Pettenkofer 

 and other savants regarding it — indeed, it was at the special suggestion of Dr. von 

 Pettenkofer that some of the observations here recorded were undertaken. 



Observations on the varying conditions of soil-moisture as indicated by water- 

 level and rain-fall have been carried out in many places in India for some years, 

 and although, owing to the difficulties incident on the beginning of any entirely new 

 series of observations, the results have not as yet been so generally satisfactory as 

 might have been desired, still a large number of thoroughly trustworthy data have 

 been already accumulated regarding the matter. These will be made the subject of 

 a special Report hereafter; in the meantime, we have limited ourselves to the 

 consideration of the phenomena observed during a complete year in Calcutta, where 

 the observations have been conducted so as to furnish data for comparison with 

 similar observations which have been, and may still be, recorded elsewhere in 

 India. 



Observations on the temperature and carbonic acid-contents of the soil have never, 

 so far as we are aware, been carried out in this country, and even in Europe they 



