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At 01:05 PM 12/28/2009, Kenneth Towe wrote, responding to Nick
Pelling's of:Dec 28, 2009, at 8:36 AM,
You are quite correct. It should have read "reasonably complete".
The problem is that we do not know what the current Enterline
hypothesis is... the one that goes together with his reasonably
complete scenario.
I had recently concluded that Ken and I must agree to
disagree. However, he now seems more open to reasonable discussion
of alternatives, and I would like to participate in that. It would
be great if he and I could collaborate in joint progress on the
Mystery of the Twinity. Crystallography aside, I believe there are
many on this list who can follow the moderate technical level of
discussion we have been having, and many who are interested. Perhaps
we can get some of them to join in. Maybe this thread IS the new conference.
First of all , I want to demonstrate my own willingness to be
flexible. The word "scenario" was originally chosen for its
indefiniteness, but I can go further and call it a "sketch." I
expect to have it change as more is learned.
The reasonably complete scenario that he published in 2002 has
been shown to be awkward in several places. As he said recently
(12/16), he is now willing to give up the idea that a scribe
quickly retraced his non-iron ink: "I'm willing to abandon that
requirement..."
"Willing," yes, but that does not necessarily mean that I have. It
depends. And it is not a "requirement" -- that's Ken's word. I
just adopted what was the going hypothesis at the time, as I've
repeated three times.
His hypothetical bleach-induced re-fluidization and lateral transfer
mechanism to slip anatase under the black line requires that the
black line be there beforehand.
Yes, but you will see in a moment that this statement contains a
veiled assumption.
Abandoning a retracing leaves no realistic alternative explanation
for the presence of a black overlying carbon line.
I think much too short shrift has been given to the separation
hypothesis. As Jacque Olin reminded us years ago, Iron gall ink
often contained carbon to make it immediately visible before the
half-hour-later chemical reaction made it permanent. But the
separation need not have happened in the fifteenth century. The
actual separation may not have happened until the putative bleach
solution re-fluidized it. Who knows (without further study) what
forces might have been going on then. But obviously one reasonable
hypothesis is that there was no overlying carbon line until the
bleached ink dried out again. After that , the surfaced carbon was
highly subject to flaking away.
Many pictures of the line show carbon particles concentrated near the
outer edge of the line. This would be a natural and expectable
effect as separation produced a lateral as well as vertical
force. The famous "mis-registration" of the overlying line in
Cahill's Plate C has been widely used to buttress a hypothesis of
(imperfect) retracing. But let's look very closely at that
picture. It's as though some force had pulled the carbon back away
from the edge before it had a chance to dry completely. Maybe a
bubble or variation of pressure from the brush. Lifting it up --
even a bristle or two from a twist of the wrist --could create a
slight suction, pulling the edges back toward the center again.
Does this kind of thinking sound so unreasonable?
Jim
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