TWO YOUNG NATURALISTS. 37 



out apparent object, and as if engaged in a fantastic 

 waltz. 



"The infinitely small," said the doctor, "perhaps 

 more bewildering than the infinitely great. These are 

 among the largest of the beings invisible to the naked 

 eye ; and what lies beyond them ? However much our 

 optical instruments are improved, however much the 

 field of our investigations is extended, always and 



ANIMALCULE IN WATER. 



always new beings are discovered whose existence 

 was before scarcely suspected, and we find ourselves 

 still on the threshold of a world that we know not 

 yet. 



" And none the less this unknown universe surrounds 

 us closely, penetrates into ourselves, and develops 

 itself even within us. It sometimes forms the very 

 ground we tread on. I was reading only to-day that 



