PKEFACE TO THE ENGLISH EDITION. 



I AM very much pleased that Dr. Orndorff has taken 

 upon himself the translation into English of the second edi- 

 tion of my book "Practicum der physiologischen und 

 pathologischen Chemie." The exact knowledge of German 

 which Dr. Orndorff has acquired by long residence in Germany, 

 together with his well-known scientific qualifications, guaran- 

 tees a correct translation. 



That part of the book dealing with inorganic chemistry 

 has not been translated, as the students in medicine in 

 America have usually completed a required course in quali- 

 tative analysis before they take up organic and physiological 

 chemistry. In the description, moreover, of the Kjeldahl 

 method of determining the amount of nitrogen in organic 

 substances, the modification adopted by the "Association 

 of Official Agricultural Chemists of the United States," which 

 is the one generally used in America, has been given. It has 

 therefore also seemed expedient to omit the Schneider- 

 Seegen method. 



A number of errors in the German edition have been cor- 

 rected in this translation ; and some additions and changes 

 have been made, those due to Dr. Orndorff being indicated 

 in foot-notes. The tables of specific gravities given are the 

 most accurate that have been published. 



