in.] THE INDUCTIVE HABIT OF MIND. 185 



rate at which the seaboard is being removed by the 

 action of waves all these are branches of study which 

 is becoming more and more important. 



And even in the study of animals and their effects 

 on the vegetation, questions of really deep interest will 

 arise. You will find that certain plants and trees 

 cannot thrive in a district, while others can, because 

 the former are browsed down by cattle, or their seeds 

 eaten by birds, and the latter are not; that certain 

 seeds are carried in the coats of animals, or wafted 

 abroad by winds others are not ; certain trees 

 destroyed wholesale by insects, while others are not ; 

 that in a hundred ways the animal and vegetable life of 

 a district act and react upon each other, and that the 

 climate, the average temperature, the maximum and 

 minimum temperatures, the rainfall, act on them, and in 

 the case of the vegetation, are reacted on again by them. 

 The diminution of rainfall by the destruction of forests, 

 its increase by replanting them, and the effect of both 

 on the healthiness or unhealthiness of a place as in 

 the case of the Mauritius, where a once healthy island 

 has become pestilential, seemingly from the clearing 

 away of the vegetation on the banks of streams all 

 this, though to study it deeply requires a fair know- 

 ledge of meteorology, and even of a science or two 

 more, is surely well worth the attention of any 

 educated man who is put in charge of the health and 

 lives of human beings. 



You will surely agree with me that the habit of 

 mind required for such a study as this, is the very 

 same as is required for successful military study. In 

 fact, I should say that the same intellect which would 

 develop into a great military man, would develop also 



