ROYAL ASIATIC SOCIETY. 



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those which deviate most in regard to time from the average 

 curve, for it will be observed that in every year there is a 

 precisely similar double rise and fall, but occasionally the time 

 when these oscillations occur is premature or is unusually 

 delayed. If it can be shewn then, that when a season gene- 

 rally healthy, in one year is found not to be so. and that such 

 an appearance is invariably accompanied by a corresponding 

 alteration in the occurrence of the dry and rainy seasons, then 

 it will, I think, be satisfactorily shewn that the insalubrity of 

 Putlam ('such as it is is oaring mainly to two causes. 



In the first place, to the im m ediate and continued action 

 of a damp atmosphere; and secondly, to malaria produced from 

 half dried-up tanks. 



In examining the diagram of 1846, we find that April, May, 

 and June were very unusually unhealthy: now it appears that 

 in that year March, April and the first half ot May, were ex- 

 tremely rainy ami unsettled, the dampness of the atmosphere 

 produced much fever, and the drying up of the tanks affected 

 the health of the station a month later than usual. Again, 

 October and November o: this year were very rainy, and the 

 latter of these months proved unusually unhealthy. 



On referring again to the diagrams, it appears from a 

 comparison of the whole, that the number of days sickness is 

 about 124 per month in a body of 100 men, which certainly is 

 not a high average, the rather when it is taken into considera- 

 tion that a very large portion of this is due to fever, which 

 very rarely proves more than a temporary inconvenience, 

 seldom proving fatal, and unproductive of those permanent 

 alterations of the constitution which follow the fevers of other 

 parts of the Island ; that each slight ailment is registered in a 

 manner utterly unattainable by those who endeavour to obtain 

 the sanitary statistics of a whole country, and that not a few 



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