(Yesterday, 03:30 PM)Stefan Wirtz_2 Wrote: You are not allowed to view links. Register or Login to view.There seem to be not any auxiliary lines for the text, no ruler was used and not always a circle in use for the round forms
Indeed. I gather that professional scribes would score guiding lines with a dry blunt stylus or blade. When they were used, they should visible under grazing light. The BL 2014 images (and the Multispectral ones) were taken under oblique light, yet there seem to be no trace of such guiding lines anywhere. Anyway, the baselines of the text are generally curved, tilted, and unevenly spaced.
(The only exception I can remember is page f67r2, which has three lines of text delimited by four guiding lines. The lines are with a ruler; one in ink, the other three with a dry point or very fine pen or pencil. However, those guiding lines are not equidistant, nor precisely parallel: the spacings, from top to bottom, are ~5, ~8, and ~6 mm at ~1/4 of the way from the left margin, and ~4.5, ~7, and ~5 mm at ~3/4 of the way.)
As for the circles, they generally were drawn with compass, apparently with an ink attachment that made very fine strokes. However, either the compass was not very solid or the vellum was shifting under it, because several circles fail to close, with ends missing each other by ~1 mm or more. Also, some parts of some circles were retraced by hand, as revealed by the thicker and jittery trace.
And the Scribe did not know how to divide a circle evenly in more than 4 parts. On that same page, the lines between the sectors are drawn with a ruler, but they don't go through the center of the circles, and the sectors have substantially different angular widths. In other diagrams, including the Zodiac wheels, the nymphs, rays, or other elements were placed around the circle with no planning; so that they start out with too much space, then get cramped up at the end, and sometimes the leftovers have to be added outside the diagram.
All the best, --stolfi