LINKS IN THE CHAIN. 



CHAPTER I. 



AN UXSEEN WORLD. 



Where the pool 



Stands mantled o'er with green, invisible, 

 Among the floating verdure millions stray." 



IF Dr. Livingstone, in the course of his African explorations, 

 were to light upon some such nation of mannikins as that dis- 

 covered at Lilliput by Mr. Lemuel Gulliver of famous memory, the 

 announcement of the fact could hardly occasion greater surprise 

 and astonishment than was felt by the philosophers of the last 

 century at the remarkable disclosures of the microscope, with 

 respect to the countless multitudes of minute forms of organic 

 life which, unseen by our feeble powers of vision, people the 

 waters of the earth, and swarm around us on every side. 



The microscope has here revealed the existence of a new 

 world of living beings, before unknown and unsuspected. It has 

 shown that the water of our roadside ditches, and stagnant 

 pools, of our lakes and streams, and of the sea itself, teems with 

 various races of microscopic beings, many of which are so incon- 

 ceivably minute, and abound in such amazing profusion, that 

 thousands of them may often be detected in a drop of fluid taken 

 up on the point of a pencil, while, within the narrow dimensions 

 of a lady's thimble, we might easily collect together a number 

 far exceeding that of the entire human population of the globe. 



It rarely happens that important discoveries are made at once 

 in all their completeness, and the discovery of this unseen world 

 of organic life forms no exception to the rule. It will be obvious, 

 indeed, that, as many of these minute beings arc sufficiently largo 



D 



