This text is presented in four parts. Each part is rather complete within itself. Thus, its appeal will reach those of varied interest in the general subject of the serology of syphilis. This of course leads to some repetition for those who view the book as a whole. Except for the very excellent chapter on the history of the Wassermann and early flocculation tests, this book deals chiefly with the author's experience in the development of the various Kahn test procedures over a period of the last 25 years.

In Part I, his new concept of the universal reaction is presented and illustrated with charts, diagrams and tables. He states that some of his previous conclusions were in error and shows that the capacity of serum to react with tissue extract antigen is not limited to syphilis but that non-syphilitic serum possesses this same capacity.The author stresses that there exists a biologically universal tendency for serum, whether human or animal,to give serologic reactions with lipid antigen.