(More comment)
Considering the sophistication and variety of almost-all-monochrome
glyphs, it seems somewhat surprising that color[u]r has not been used more
to give meaning. With modern colo[u]r printing and displays, at least we
now have affordable technology to support chromatographic scripts.

Digging into the history of European musical notation does reveal use of
red ink in a few instances. (Look into "hemiola", iirc.)

One wonders about use of color specifically to convey meaning in old
manuscripts other than musical.

Then, of course, mechanical business machines, including many typewriters,
had red and black ribbons, and "dot matrix" impact printers had four-color
ribbons, developing further on color-ribbon technology. (Btw, those
multicolor ribbons have flexible barriers to keep the inks from bleeding
into each other. Never occurred to me until I learned about it.)

Nicholas Bodley <#o#> Waltham, Mass.
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