Thank You Denise,
I was particularly gratified that W. Abney specifically confirmsthe importance of a standing sheet of water as a test for cleanliness of glass plates. I have sulfuric acid (Wall) and will get some Nitric acid (Abney). But really, the acid/base cleaning method is very similar to the way in which I already clean glass. But I use oxalic acid and phosphoric acid, at different times.
Bill