PREFACE TO THE SECOND EDITION. 



It is gratifying to the author that a second edition 

 is demanded, and especially that the views advanced in 

 this work are being very generally accepted by micro- 

 scopists throughout the world. 



The first edition of this work having been exhausted 

 some time has given occasion for such corrections as 

 crept into the former edition in spite of the utmost 

 care. As a hand book for beginners it is a pleasure 

 to know that it has prevented unlearning many now 

 obsolete notions. 



The wonderful advances recently shown especially 

 by makers of stands does not now perhaps warrant 

 the strong bias made in the text. The best stand 

 to-day may not be to-morrow. The general rules for 

 selection, however, hold good. 



If it continues as " a help to see" none will rejoice 

 more than THE AUTHOR. 



