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CHAPTER V. 



On Staining Fluids, and Staining. 



THE value of the various staining processes 

 consists in the perfection with which the differen- 

 tiation of the tissues is accomplished, and their 

 features and structure brought out. In the stain- 

 ing of tissues it is all important that the nuclei of 

 the cells shall be deeply stained, whilst the cellular 

 structure is clearly defined. 



Staining is an art, requiring much experience 

 and great delicacy of manipulation. It is one thing 

 to colour a section or a tissue, quite another to 

 stain, and especially to double-stain and differen- 

 tiate it. In double and triple staining the great 

 desideratum is to secure a thoroughly good nuclear 

 stain as the ground colour, and to supplement this 

 with a delicate tint, or tints, which shall prove a 

 good contrast to the first stain and thoroughly 

 differentiate the tissue without diffuseness. 



For staining the nuclei of the cells, for beauty 

 and permanence, no staining fluids have yet been 

 discovered to surpass haematoxylin, carmine and 

 picro-carmine. The brilliancy of carmine has its 

 advantages in many cases, whilst the delicacy, the 



