126 THE MICROSCOPE. 



"^tvlnxss. 



The Microscope and its Revelations. By William B. Carpenter, sixth 

 edition, 26 plates, 500 wood-engravings, pp. 8S2. 

 Presley Blakiston, Philadelphia, 1881. Price $5.50. 



It is with pleasure and pride that we point to the voluines of 

 Carpenter in our library. In this edition we notice as the frontispiece 

 a beautiful plate of volvox, and no less than fifty new wood-engrav- 

 ings have been added throughout the book. Much new matter is 

 introduced under the Bacterium group and in very many places the 

 text has been altered. Great changes have been made in the 

 methods of preparing, staining, mounting, and collecting of objects. 



The reader finds much new matter in chapter IV and much that 

 will go to establish the opinion that because an objective has wonder- 

 ful "resolving" power when applied to the most difficult tests, it is 

 no sign that it is the best objective for biological use. Mr. Dallinger 

 has been able to do more with a dry ^Jjth of "moderate angle" than 

 would have been possible for him to do with an oil-immersion TjVtn 

 of the same makers with far superior resolving power. Dr. 

 Carpenter defends, better than ever, his old theory that moderate 

 angular apertures are the best for biological work. 



The chapter on the application of the microscope to Geology 

 is very satisfactory and adds greatly to the vahic of this edition. 

 Bearing in mind the changes that have been made and the amount 

 of new matter added we must declare that those who already possess 

 an earlier edition of this work cannot afford to be without this one, 

 and those who have never possessed a volume of Carpenter should 

 procure a copy without delay. We cannot pass this subject by, 

 however, without regretting that Dr. Carpenter did not recognize 

 more of our American instnmients He mentions but one, and that 

 one no better than many others. A half dozen makers in this 

 country could show better and cheaper microscopes than he exhibits. 

 However we can easily forgive this for the many good things he has 

 given us. 



Dr. Carpenter is our highest authority on general microscopical 

 matters and we unhesitatingly declare this to be the best book of 

 its kind in the English language. 



