While laboratory men who are looking at spinal fluids every day have no difficulty in quickly distinguishing between these cells without staining, clinicians of less experience will often find a differentiation troublesome, even with the high power. The use of acetic acid or Turk's solution has the obvious disadvantage of further diluting what may be a fluid of low cell count.
I have found no convenient method in the textbooks on clinical diagnosis, and the following procedure which, from its simplicity, is probably being used independently by many men, I have not seen described:
The fluid is taken in two test tubes. To one of these, containing about 2 c.c., is at once added one drop of Loeffler's methylene blue, and the tube shaken gently. The second tube is saved for other tests. Examination after two minutes reveals the nuclei of the white cells staining distinctly, so that they may