260 THE AMERICAN MONTHLY [Aug 



of Zeiss, Leitz, and Reichert. A great many slides are in- 

 cluded. This firm has a slide-lending- department. A no- 

 ticeable feature is an exceptionally complete series of rea- 

 g"ents and stains prepared by the most scientific methods. 

 There is a special catalog^ue of the necessary apparatus for 

 the study of the effects of malaria upon the blood, bacteri- 

 olog-ical outfits, etc. The preface states that microscopes 

 are included that are suitable for engineering-, brewing", 

 baking-, paper-making-, and other industries. 



Micro-organisms. — The Microscopy of Drinking- Water, 

 by G. C. Whipple, is published by John Wiley & Sons. 

 While the importance of the chemical and bacteriol6g-i- 

 cal analysis of water has long- been recog-nized, the study 

 of the lower forms of animal life included under the terra 

 "microscopy of water" has received far too scant atten- 

 tion as a branch of hyg-iene. It is beg-inning- to appear 

 that quite as accurate estimates of the purity of drinking- 

 water may be based upon its microscopy as upon the some- 

 what uncertain and more laborious results of chemical 

 and bacteriolog-ical analysis. On this account the appear- 

 ance of an elementary work upon the forms of animal life 

 commonly found in drinking- water, and the significance 

 attaching- to their presence, is most acceptable to a larg-e 

 class of readers who are broug-ht in contact with this sub- 

 ject. The present volume is specially adapted to the needs 

 of the medical profession, as the practical use of the data 

 presented requires only a moderate biolog-ical training-. 

 The first half of the work contains a g-reat deal of useful 

 information reg-arding- the objects and method of micro- 

 scopical examination of water, the factors g-overning- the 

 appearance of micro-org-anisms in water, the orig-in and 

 sig-nificance of odors in water, and the method of storing- 

 surface water. The remaining- chapters are devoted to an 

 elementary description of the principal g-enera of micro- 

 org-anisms, beautifully illustrated by twenty-nine full-page, 

 half-tone pictures. The volume will fully repay careful 

 reading-, is sufficiently complete for an elementary book of 

 reference, and should find a place in every medical library. 



