IV PEEPACE. 



microscopic science, and will be well prepared to 

 extendhis independent researches, without any other 

 limit than that which the finite, though vast, sphere 

 of study itself presents to him. 



The staple of the work now offered to the public 

 consists of original observation. The author is far 

 from thinking lightly of the labours of others in this 

 ample field ; but still, it is true, that respecting very 

 many of the subjects that came under his notice, he 

 found, in endeavouring to reproduce and verify pub- 

 lished statements, so much perplexity and difficulty, 

 that he was thrown back upon himself and nature, 

 compelled to observe de novo, and to set down 

 simply what he himself could see. The ever- 

 accumulating stock of observed and recorded facts 

 is the common property of science ; and the author 

 has not scrupled to reproduce, to amplify, or to 

 abridge his own observations which have already 

 appeared in his published works and scientific 

 memoirs, as freely as he would have cited those of 

 any other observer in which he had confidence, and 

 which were germane to his purpose. Yet, in almost 

 all cases, the observations so used have been sub- 

 jected to renewed scrutiny, and have been verified 

 afresh, or corrected where found defective. 



In order to relieve as much as possible the dryness 

 of technical description, a colloquial and familar style 

 has been given to the work ; which has been thrown 

 into the form of a series of imaginary conversaziones, 

 or microscopical soirees, in which the author is sup- 

 posed to act as the provider of scientific entertain- 

 ment and instruction to a circle of friends. It is 

 proper to add, however, that the precision essential 



