178 



CEYLON BRANCH 



it appears that during the former period the station is less 

 healthy than during the latter. I have attempted to show the 

 relative positions of these seasons in the annexed sheet. The 

 most striking features in this comparison, are, first, the cor- 

 respondence in number ; secondly, the want of correspondence 

 in time; and thirdly, what appears least explicable, a 

 want of apparent rule in these variations. A more care- 

 ful examination of the subject however explains, I think, this 

 anomaly : thus we find that during the great dry weather, that 

 is, between May and October, the first month is healthy, the 

 next three much less so, and the last two again very salubrious. 

 From this I would deduce that a great portion of the sickness 

 during June, July and August, is caused by the drying up of 

 tanks in the neighbourhood, and also perhaps by malaria 

 transported by the north-east monsoon from the long track of 

 low swamp jungle which extends towards Anoorajapoora. In 

 September and October the tanks are on the other hand quite 

 dry, the shell-fish and plants are no longer putrifying in the 

 sun, and the station is healthy. This does not occur however, 

 till after about four months of nearly perfect drought. In 

 November, December and January, there is almost constant 

 rain, exposure to which produces catarrh, fever, &c. ; and by 

 a reference to the diagram on which the average appearances 

 of fever are detailed, it will be observed that this disease is 

 more prevalent during and immediately after the great rains, 

 than at any other period. 



During February and March there is little rain, there not 

 being time however for the tanks to dry up entirely, the state 

 of health is almost identical with that of June, July and Au- 

 gust when, as shewn, the circumstances are in this respect 

 precisely similar. 



To put this hypothesis to the test, I have carefully ex- 

 amined some of the diagrams for individual years, especially 



