[Michael R 1974]

The "encapsulating" compounds are what I expected were involved in Kodak's single packaging. I assumed something like this kept the sulfite from dissolving before the Metol. It was just a guess though as I don't have anywhere near the chemistry knowledge required to make that claim with any kind of certainty.

Also interesting is the wording used by Haist when he talks about mixing practices and why Metol must be dissolved before sulfite. He says the Metol must be dissolved first because it precipitates in a sulfite solution. This seems an odd choice of words since in my mind "precipitation" is when a substance already dissolved comes out of solution. If Metol actually precipitated in sulfite solutions than as Gerald says, it wouldn't matter if the Metol went in before or after the sulfite. Again though, I'm in over my head as far as the chemistry goes so what I'm saying might be nonsense.