Herculean Task!

Hi there. I'm trying to track down a specific proposition in the Bodleian manuscript of Euclid. (Thank you, Libraries Without Walls.) Problem is, I don't read classical Greek, and I haven't the faintest clue how something like this would be numbered. Luckily, the oldest printed version had numbered propositions, and I was able to hunt it out just by flipping through pages on LWW.

Can anyone help me find Proposition 20 in Book IX ?

The proposition is on Perseus here. As well, in more modern style, here.


x-posted to bibliophyles