He guessed that the symbols represented the name of the earlier Egyptian ruler Ptolemy, since Ptolemy was also written in Greek on the stone and was indeed a Greek name.
And Yang, did actually prove that these hieroglyphs represented sounds rather than whole words.
Strangely though, he gave into the dominant thesis of the day that hieroglyphs were pictographs.
He actually dismissed his own finding as an anomaly because the Ptolemy dynasty was Greek, not Egyptian.
In other words, he figured it was an exception to the rule.
It was phonetic because it was Greek not Egyptian.
How else could an Egyptian depict a Greek name other than spell it out?
And that brings us to the hero of our story, Jean-Franrois Champollion.
Champollion built on Yang's work, showing that different hieroglyphs spell the name of the kings or queens like Alexander or Cleopatra.
But his critics noticed that these were still not traditional Egyptian names.
He hasn't done anything more than Yang has been able to do, so he couldn't disprove the dominant theory.
Then, in 1822, Champollion was shown a set of hieroglyphs that contain traditional Egyptian names.
The first two of the symbols were unknown, but Champollion knew that the repeated hieroglyphs to the far right symbolized an 's' sound.
He then drew on his linguistic knowledge to arrive at the solution to the problem.
You see, unlike any of other scholars who have tried to crack the code, Champollion happened to be fluent in Coptic.
He wondered, and this was the real breakthrough, if the Coptic was the language symbolized by the hieroglyphs on Rosetta stone.
And if so, then perhaps that first disc-shape symbol might represent the Sun.
And the Coptic word for Sun is 'ra' .
See where this was it headed?
So if the symbol were Coptic, the first symbol would be 'ra', and then an unknown symbol followed by a double's' sound.
Was this, Champollion wondered, the name "Ramses"?
He was eventually able to confirm that it was.
So, he had figured it out.
Hieroglyphs were mainly phonetic, they represent sounds not pictures, and the underlying language was Coptic.
A lot of work remained, but Champollion had cracked the code.