he has read its delightful pages in youth, read once again—­that hitherto unrivalled little monograph, White’s ‘Natural History of Selborne;’ and let him then try, by the light of improved science, to do for any district where he may be stationed, what White did for Selborne nearly one hundred years ago.  Let him study its plants, its animals, its soils and rocks; and last, but not least, its scenery, as the total outcome of what the soils, and plants, and animals have made it.  I say, have made it.  How far the nature of the soils and the rocks will affect the scenery of a district may be well learnt from a very clever and interesting little book of Professor Geikie’s, on ’The Scenery of Scotland, as affected by its Geological Structure.’  How far the plants and trees affect not merely the general beauty, the richness or barrenness of a country, but also its very shape; the rate at which the hills are destroyed and washed into the lowland; the 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 knowledge 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 into a great naturalist.  I say, intellect.  The military man would require—­what the naturalist would not—­over and above his intellect, a special force of will, in order to translate his theories into fact, and make his campaigns in the field and not merely on paper.  But I am speaking only of the habit of mind required for study; of that