Bill,

Part of the question in your OP referred to the quality of glass required for dry plates. That question has rumbled around in my brain for years, but never floated high enough to prompt the necessary lit search. Thanks for the prompt!

There's not much information. I think it's because glass technology is one of those areas most of us take for granted. But, it has changed considerably since gelatin emulsion was first poured on glass. At any point in the timeline, photographic companies used the best glass-for-the-price available to them. In the 1930 edition (English translation) of 'La Technique Photographique', L.P.Clerc wrote:
"The glass used in the manufacture of photographic plates is specially manufactured, and is, in fact, the monopoly of certain Belgium firms. It must be fairly flat, of uniform thickness, almost colourless, and as free as possible from bubbles or black spots. These qualities are rarely united in one glass, even in the highest qualities for picture framing, which are of much better quality than window glass. The sheets of glass, received in crates, are sorted according to thickness and quality, and stored for distribution as required." p152.

It's unclear what technique(s?) were being used to make the glass.

In Clerc's 2nd edition (1937/1946 reprint) he added a footnote: "Drawn glass, which is now beginning to be more widely used..."p157. According to the Wiki machine, 'drawn glass' (Fourcault process) was developed in Belgium in the early 1900's. About that time, machine-rolled glass became more available. It was cheaper than hand-rolled glass, but the initial capital investment was huge, and only a few companies were involved. Float glass, which is probably all most of us recognize as sheet glass, wasn't invented until the 1950's.

Back to the issue as far as artisan emulsions are concerned -- any green color a glass plate might have won't be a problem worth noting for colorblind/'ordinary' or ortho emulsions, and might even be to a slight advantage.