NOTES ON THE GRAM STAIN WITH DESCRIPTION OF 

 A NEW METHOD^ 



VICTOR BURKE 

 From the Department of Pathology, Stanford University, San Francisco 

 Received for publication June 2, 1921 



An examination of the literature concerning the Gram method 

 of stainhig bacteria and of the methods of making the stain in 

 various laboratories reveals the fact that a successful stain, i.e., 

 one giving sharp differentiation between Gram positive and Gram 

 negative organisms, can be obtained by several methods. A 

 comparison of these procedures indicates that in a successful 

 method each step is properly coordinated with and influenced 

 by the other steps in the process. One step can be modified if 

 other steps are also properly modified. This fact has been 

 recognized and made use of in the various processes employed to 

 improve or shorten the process of making the Gram stain. 



Of all the various methods advanced none has successfully 

 eliminated the personal factor. A satisfactory stain, especially 

 of pus smears, depends to some extent upon the skill of the 

 operator. Any one procedure has to be more or less modified 

 depending upon the type of smear to be stained. For this reason 

 the untrained assistant can not always be depended upon to 

 produce satisfactory results by following any method so far 

 advanced. 



The skill of the operator, aside from his knowledge of the organ- 

 isms to be examined, depends, upon the proper control of decolor- 

 ization and the ability to detect any defect in the prunary stain 

 used. 



' Aided by funds from the United States Interdepartmental Social Hygiene 

 Board for Research in the Prevention and Cure of Venereal Diseases. 



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