The Microscope. 215 



XJhlworm, of Cassel, Prof. Teitckart, of Leipsig, and Dr. Loftier, of 

 Berlin. These names suffice to establish the character of the jour- 

 nal. 



Many medical schools also have recognized the demand of 

 students for the practical study of bacteriology and have established 

 well equipped laboratories and- appointed teachers. 



The apparatus necessary to pursue the study is elaborate, and 

 the optician is put to his best to produce condensers and objectives 

 of the high power and quality demanded. There is no field in 

 microscopy which offers such a rich harvest in all departments of the 

 science as bacteriology. The cultivation, isolation, staining and 

 mounting of microbes, demand the most delicate " and skillful 

 technique, while their study with the microscope requires lenses of 

 the highest quality and the most exact manipulation of condensers 

 and other necessary apparatus. This branch of microscopy then, 

 offers to the expert opportunities for the display of his highest skill, 

 and we commend it in strictly scientific sense to all workers in and 

 out of the medical profession. The sanitary questions involved in 

 the discovery of bacteria and the study of their life histories are of 

 such import to the human race that unless some future discovery 

 overthrows the present idea of their etiological significance, the 

 study of microbes will hold for some years to come the first place in 

 microscopical science. 



Among the recent original studies in bacteriology are two which 

 are of great importance to preventive medicine. Dr. T. Mitchell 

 PiTidden publishes in the Medical Record of March 26 and April 2, 

 an exhaustive study of bacteria in ice, and the destructive influence 

 of cold upon these organisms. The article details a new method of 

 water analysis. In examinations of potable water it has been cus- 

 tomary to depend upon chemical analysis to determine their proba- 

 ble salubrity, and much time and skill have been employed in per- 

 fecting the delicate tests. The presence of organic matter has been 

 looked upon as indicative of the presence of specific poisons danger- 

 ous to health, but chemical analysis can determine only inferentially 

 the presence of microbes. With the new method of analysis it is, as 

 Dr. Prudden says, " no longer necessary to infer the presence of 

 bacteria in a given sample of drinking water from its organic con- 

 tents, but the bacteria may be actually seen, counted, and their 

 species and actions on the animal body definitely determined. The 

 new method of water analysis, by which its living bacterial contami- 

 nations are determined and studied, is called the biological analysis.''^ 



