[Design of Marci Letter]

[proto57]

There are many things that could cause staining like that over the course of hundreds of years. Smoke exposure, liquid, dirt, to name just a few. The next question from someone will certainly be - can it be tested? Sure, but I guarantee you that there's no way the Library would agree to the time, expense, risk, and staff time that would be required when the outcome really wouldn't add anything to our understanding of the letter.

Of course it can be many things, but the "something there" is there, where it is seems to me to be very important. I mean, why would "Smoke exposure, liquid, dirt...", anything, just "happen" to lay near the fold line of the tab, but not cross it? Here is the entire length of the tab in the picture you took on the light table, with the brightness and contrast played with to be able to see it as clearly as possible (I think, others could play with this image themselves, and maybe get more out of it):

   

For instance, to your suggestions for alternatives to a glue, or paste, such as dirt or water stains, I can't see how that would end up looking like what we see, because it does not cross the fold at any point, one, and two, it is not anywhere else on the letter like this: not in color tone, or in a slightly irregular line like this.

Now working against this being an adhesive might be "why?" would it not be more centered in the tab's width? Well maybe that would imply how it was attached in the first place, such as one edge being held down, the other tipped up to apply glue. Or for a million other reasons.

In any case, I think it could yield important clues to know what this is. There are so many non-invasive, non-risk methods of determining the makeup of substances on paper, which may determine this. If it were a hoof or hide glue, albumen from egg white, and so on, this could tell us a lot.

And yes, of course it is already assumed that the letter was in this book originally, and refers to this book... but that is all an assumption, with varying degrees of plausibility. But it has not been determined as factual, only assumed. Here is a chance, with the proposals, suggestions, observations which asteckely has been making, and I feel that it would be excellent to try and learn the reality of the letter, the folds, the seals, the tab, the cover for that matter... all while we can, especially when it is not harmful to do many tests, and take macro photographs, rather than continuing to assume the outcome without trying.

"Never assume" is often said, but most of what we think we know about the Voynich is based on assumptions. Why not dig deeper, and either buttress those assumptions and validate them; or discover new facts about all this that might help finally solve this mystery? The opportunity is right in front of us.