292 DE. VINCENT HAEtllS. 



On Double Staining Nucleated Blood-Corpuscles 

 with Anilin Dyes. 



By 



Vincent Harris, 9I.1>«, 



Demonstrator of Physiology at St. Bartholomew's Hospital. 



The usefulness of the process of staining tissues with several 

 dyes has been abundantly proved. The general effect aimed 

 at is the staining of each separate part in a different colour, so 

 that for the purposes of histological demonstration each shall 

 be distinct and clear. In the use of certain of the most com- 

 monly employed and easily manipulated dyes, e. g. hema- 

 toxylin and picrocarmine, it is believed that a definite effect 

 may be always calculated upon when they are used in combi- 

 nation. With anilin stains, however, the results arrived at 

 appear to differ very materially if the methods of employment 

 are made to vary in even a very slight degree, and this has 

 been one of the causes of the restricted use of very beautiful 

 staining colours. It has been shown by several experimenters 

 that with combinations of anilin colours, there is a tendency 

 at any rate for certain dyes to pick out and stain different 

 parts of a tissue ; but I think I am right in believing that no 

 certain result has hitherto been expected, except in the case of 

 a very few combinations. 



There is no doubt that unless more definite results be 

 obtained with combinations of these dyes, the hope that with 

 them it will be possible to pick out each element of a tissue in 

 a different colour, and each kind of morbid growth in a similar 

 manner, will be long deferred. 



The following notes were made during a series of experiments, 

 the object of which was to find out the best combination of anilin 



