[Histonet] Movat's Pentachrome question

[Monfils, Paul]

Does anyone do Movat's Pentachrome stain?  I have a researcher who wants to
do it.  My question involves the "alkaline alcohol" the procedure calls for.
The protocol says to add ammonium hydroxide drop by drop to 95% ethanol
until the pH reaches 8.0 or higher.

Question 1, a theoretical one - How can you accurately measure pH in a
nearly water-free solution?  Presumably an ionic compound would not ionize
very well in such a solution?

Question 2, a practical one - When I put the pH probe into 95% ethanol, the
meter already reads higher than 9.0, even without adding any ammonium
hydroxide. Is this your experience?