92 The Preparation of Microscope Slides 



ing solutions are used one after another in such a manner that the nuclei 

 and all the elements of the plasma are stained in sharply contrasting colors. 

 The stains used in botany, naturally, are quite different from those used 

 in histology and pathology and are given immediately following this sec- 

 tion. Many hundred complex stains are in the literature and will be 

 found in Gray's "Microtomist's Formulary and Guide," where several hun- 

 dred more stains of specific application are also given. Here it is intended 

 to present only three stains, which are so simple to use and so excellent 

 in their results that they should be known to everyone. The first of these 

 is: 



Mallory's Triple Stain: 



First staining solution 



1% acid fuchsin 

 Differentiating and mordanting solution 



1% phosphotungstic acid 

 Second staining solution 



Water 100 ml 



Aniline blue 0.5 g 



Orange G 2 g 



Oxalic acid 2 g 



Method of Use 



1. Accumulate sections for staining in water. 



2. Stain them in the first staining solution for 2 min. 



3. Rinse the slides thoroughly in water. 



4. Transfer them to the phosphotungstic acid for 2 min. 



5. Give the slides a very quick rinse in water. The purpose is to remove 

 the phosphotungstic acid from the slides, not from the sections. 



6. Transfer to the second staining solution for 15 min. 



7. Wash the slides in water until no more color comes away. 



8. Take each slide individually and dip it up and down in absolute 

 alcohol until it is differentiated. This may be seen clearly with the naked 

 eye, for the slide, which is a muddy purple when differentiation starts, 

 suddenly clears to show bright-blue and bright-red areas. 



9. Transfer the slide to xylene, which stops differentiation. 



When using this stain for the first time, it is well to transfer sections to 

 xylene and examine them under the microscope before differentiation is 

 complete and then to put them back into absolute alcohol to complete the 

 differentiation. A successful slide will show nuclei in red, cartilage and 

 white fibrous connective tissue in blue, nerves and glands in various shades 

 of violet, muscle in red, and erythrocytes and keratin in orange. The only 

 disadvantage of the technique is the rapidity with which the blue color is 



