DEMONSTRATING THE NUCLEI OF NERVE FIBRES. 217 
An Easy Way of Demonstrating the Nuclei of 
Nerve Fibres. 
By 
Henry E. Relmrn, 
Student of Medicine. (From the Physiological Laboratory, King’s 
College, London.) 
While attending the histology class this summer, I, in 
common with my neighbours, found great difficulty in render- 
ing visible the nuclei of teased, fresh nerve fibres. Using 
gentian violet as recommended in Sir Edward Schafer’s 
* Essentials of Histology/ the nerve fibres were almost 
uniformly stained, and the nuclei did not stand out convinc- 
ingly. I tried other stains with equally disappointing results, 
and at last, in desperation, I used a mixture of nearly all the 
stains on the table (Ehrlich’s haematoxylin, methylene blue, 
and alcoholic solution of eosin) and thus obtained a prepara- 
tion in which blue nuclei stood out prominently on a reddish 
background. The preparation was shown to Dr. de Souza 
and Prof. Halliburton, who suggested to me that I should 
proceed to investigate the matter and ascertain what was the 
cause of success in this “ blunderbuss ” experiment. 
Without going into all the details of the numerous prepara- 
tions I made subsequently, I may state at the outset that the 
principal factor is the alcohol, in which, in my first successful 
experiment, the eosin had been dissolved. Aqueous solutions 
of eosin are quite as ineffective as the other stains. Fresh 
nerve fibres (and especially their nuclei), teased on the slide 
in the usual way, stain with great difficulty. But the nuclei 
stain readily with practically any dye (methylene blue, haema- 
