6 INTRODUCTION. 



Animals; which are very far from having been completely 

 studied ; and to these the Microscope will be found a never- 

 ending source of amusement and instruction. The most curious 

 facts we possess in regard to the influence of light on the deve- 

 lopment of the Vegetable structure, were ascertained by the 

 observation of one of its commonest and simplest forms (VEGET. 

 PHYSIOL. . 95) ; and the progress of discovery is almost daily 

 revealing to us something new in the structure of animals with 

 which we imagine ourselves to be well acquainted. A very 

 limited knowledge of names and classification is required for the 

 successful pursuit of such inquiries ; although there is doubtless 

 a great advantage in a previous acquaintance with the general 

 principles of Natural History, both in preserving the inquirer 

 from erroneous conclusions, in directing him to new subjects for 

 observation, and in heightening the pleasure which he derives 

 from his pursuit. But such a view need not involve details 

 which are burdensome to the memory ; nor diminish the feeling 

 of freshness, which we derive so much more strongly from 

 surveying the wonders of Nature for ourselves, than from 

 becoming acquainted with them through the writings of others. 



Thus, although no one can go far in the scientific pursuit of 

 Natural History, without some knowledge of names and of clas- 

 sification, yet this is but little required by those who pursue 

 certain departments of it for their own pleasure and improvement. 

 For it cannot be too constantly borne in mind, that in its present 

 state (which is much less perfect and complete than that of almost 

 any other science), there is ample room for the labours of all who 

 devote themselves to it as their regular object of pursuit, and with 

 the intention of raising it in the scale of the sciences, much more, 

 therefore, for the less constant inquiries of those, who seek but 

 for refreshment and novelty by occasionally turning to the study 

 of Nature, from the harassing cares of business, or the wearying 

 monotony of a handicraft occupation, and who are content 

 with the humbler but not less honourable task of collecting and 



