10 INTRODUCTION. 



perfect development, the love of Infinite Wisdom and unbounded 

 Power, or the love of God." But it is not every mind which is 

 conscious of this high and noble aspiration. In many it exists 

 without the knowledge of its possessors, and needs to be 

 awakened from its dormant condition. In some it seems almost 

 or altogether deficient. It cannot be amiss, then, to hold out 

 some of the more direct advantages which attend the cultivation 

 of Natural History. These are twofold : the first bearing upon 

 Man's corporeal wants ; the second upon his mental and moral 

 state. A single illustration, having reference to each of these 

 points, must here suffice. 



There are many species of Insects, whose voracity (especially 

 in the larva state) is so great that, when they are present in 

 large numbers, they become a source of the most terrible devas- 

 tation. We have examples of this kind, on a small scale, in our 

 own country. Thus the caterpillars of the Beetle kind, and especi- 

 ally of the Cockchafer, would speedily destroy the roots of all our 

 corn and grasses, were they not themselves eagerly sought after as 

 food by the Rook and other birds. It is true that, when the 

 supply of these is exhausted, the Rook will support itself upon 

 new-sown wheat. But the injury which it thus does to the 

 farmer is as nothing compared with that from which it saves 

 him ; and if this tribe of birds were to be extirpated, a famine 

 would speedily follow. In many parts of this country, however, 

 popular ignorance has prevailed so far as to cause the destruction 

 of rookeries, under the idea that the birds devour a large quan- 

 tity of grain ; but so speedy has been the multiplication of the 

 real enemies of the agriculturist, when no longer kept within 

 limits, that the restoration of the birds has been, in every 

 instance, petitioned for within a few years. The larvae of the 

 Turnip Fly committed the most serious ravages in some of the 

 eastern counties of England, a few years since ; and no method 

 was found so effectual as the turning a large number of Ducks 

 into the turnip-fields ; for these birds, being the natural enemies 



