How good is your pareidolia?

[Jorge_Stolfi]

While [retracing with 0.1 mm precision] is humanly possible, I'm not sure it was practically feasible. I can barely achieve 0.15 mm precision with a very good tool and a magnifying glass for a one time job performed with extreme care. [...] with a quill there is an additional complication, one would have to match not only the position, but the width of the stroke as well. I have some limited experience with the quills (both making and writing), and I have practical understanding of how they work, I think it would have been extremely hard to pull off this kind of retouching/retracing even for a professional scribe.

OK, maybe not everybody can do it.  But the original Scribe did that routinely.  He controlled the position and width of his strokes with ~0.1 mm precision, at normal writing speed, without a sweat.

When writing a Ch,  for example, he would write an e and then an h with the tip of the ligature precisely touching the tip of the e.  Ditto when writing s, t, etc. And the original figure outlines are generally ~0.2 mm wide, independently of direction.

In the first example of You are not allowed to view links. Register or Login to view., while the retracer went off-course on some glyphs, he precisely retraced many others.  Had he used a broader pen (instead of a narrower one) and ink of matching color, it would be hard to tell that those glyphs had been retraced.

One thing I think could happen, is while the ink was still wet on the page, the scribe added a touch of ink with the tip of the quill to some strokes.

That certainly did happen;

Another common cause for variations in stroke weight (darkness and/or width) is the normal ink flow dynamics.  After the pen is recharged by dipping it into the inkwell, the first word or two come out heavier than normal, because there is some ink sticking to the very tip of the nib.  But in that brief interval the weight of the strokes drops to the "normal" level.  From then on, the flow of the ink -- from the little reservoir up into the quill's hollow down to the tip -- is regulated by the opening and closing of the two tines of the nib, as the pen is is pressed down and lifted off.  That steady-state regime continues for a line or two, until the reservoir gets exhausted.  Then the strokes quickly become fainter and fainter.  At that point the Scribe would recharge the pen, and the cycle would repeat.

   

(However, a really good scribe would recharge well before the strokes started to fade, and he would also scribble a bit on a separate scrap paper after recharging to get into the "normal" regime before resuming the work -- so that the weight would be uniform through the whole document.)

Another cause of weight variation is the Scribe "back-tracing" -- going back and retracing some glyph or stroke that he just wrote, because it came out malformed or too faint. 

And then there may be cases where the Scribe could not figure out a glyph from the draft, so he left that position blank, later asked the Author, and then went back and filled the gap -- with a freshly recharged pen.

And it may also have happened, as you say, that a stroke became darker than normal by accident --- the pen hit some imperfection of the vellum, or the Scribe sneezed, or whatever...

BUT STILL, besides all those "original" weight variations, there are many cases where the only explanation is that the strokes were retraced by someone who knew even less about the Voynichese script and figures than we do now, and did not have access to the draft or the Author.  You have two such examples in that You are not allowed to view links. Register or Login to view. clip (B and I), within a few square cm...

By the way, I used to be in "there is retouching in the MS" camp, but I changed my mind after this thread: You are not allowed to view links. Register or Login to view.  There are some images of ink variation in other manuscripts there and some examples of retouch jobs.

Funny, my reading of that thread is that it rather supports my pareidolia.

In You are not allowed to view links. Register or Login to view. from the VMS, the "oCta" was obviously retraced.  In the original, the last glyph of the word was a y, but the Retracer (like us now) did not see its tail, and thus "restored" it as a.  Also the glyph before the t may have been an e, which the Retracer mistook for a C... 

In tYou are not allowed to view links. Register or Login to view., from another manuscript, those abrupt weight changes may have indeed been quirks of the ink flow... but they may also be a case of the whole text having been retraced, to fix the poor handwriting of the scribe who first did the job. 

For instance, in the p198b fragment, note that the left half of the "9" glyph is narrower and lighter than the right half, and its shape is rather "lame".  Imagine the whole text being written with such strokes.  I think it would make sense that another scribe was charged with retracing the whole thing with a slightly wider pen and more decisive strokes.

But, as in the VMS, the Retracer could not redo the tails and plumes, because the slower retracing would have made them fat, with blunt ends.

Anyway, that example was indeed fully retraced, it probably happened shortly after the original scribing, and using the same ink.  Which is not the case of much retracing in the VMS.

Hypothetically, the original [VMS] writer looked at yesterday's dry pages and added a few improvements. Yes, there are ink variations, certainly there can be retouches and corrections, but what is the chronological evidence to show a timespan of months, years or centuries?

The evidence is that the VMS Retracer made many mistakes that can be explained only if parts of the original had faded so much that he failed to see them, and he had no access to the draft or Author.

In that You are not allowed to view links. Register or Login to view. clip that I posted, mistakes B and I happened because insects had completely eaten part of the original glyphs.  You can see the scraping clearly in other parts of that page, and even more of it on page f1r.  The damage was such that the Retracer mistook the remaining half of one plume as being attached to the wrong glyph by the wrong end (the B "weirdo") and failed to see the surviving tip of the other plume (the I case).  It is unlikely that the damage happened while the original Scribe and Author were still around.

Sure, but if the ink was light in the first place, the original writer may have though it was too pale to last the coming years / centuries and gave it a second stroke, perhaps the next day or a decade later.

Again, there are indeed cases were the best explanation is that the original Scribe himself retouched glyphs, because they came out crooked or too faint.  But that cannot explain cases B and I,
or even the other cases, in the clip I posted.

All the best, --jorge