This disk shows us the 16th century (1500 to 1599); it’s disk 16 of the T5 “Centuries” series.
(Image: © Copyright Gregory Williams (Flickr) and licensed for reuse under Creative Commons Attribution-NonCommercial-NoDerivs 2.0 Generic (CC BY-NC-ND 2.0))
At the top right of the inside of the triangular area, you can see the symbol for Mercury. And at the opposite side is Venus. Down at the bottom is the Earth, with the Moon orbiting it.
So I think that this disk is devoted mostly to the Copernican astronomical revolution. The Wikipedia says:
Copernican heliocentrism is the name given to the astronomical model developed by Nicolaus Copernicus and published in 1543. It positioned the Sun near the center of the Universe, motionless, with Earth and the other planets rotating around it in circular paths modified by epicycles and at uniform speeds. The Copernican model departed from the Ptolemaic system that prevailed in Western culture for centuries, placing Earth at the center of the Universe, and is often regarded as the launching point to modern astronomy and the Scientific Revolution.
The text in the three bars can be decoded using our key, as follows:
h w a v e s o f f ->
w s t i l l s u c ->
l e f o r t h e “ -> flipped vertically
And the text for this disk reads:
.....w still such waves of f... ......le for the “
which makes a bit of sense.