This is from an explanation of the six Ptolemaic statements, the one that concludes that the world is round (terram esse rotundam).
Terra tamen ob duritiem non potuit perfectam rotunditatem adipisci: sed montium eminentiae, aut valles ad tantam mollem collatae non sentiuntur.
Here's what I have so far:
The land, however, because of its hardness, cannot acquire perfect roundness, but the prominences of mountains and valleys are not perceived...
...compared to such softness?
What softness? I don't see any softness mentioned in the paragraph. I know what it should mean: compared to the magnitude of the Earth's diameter. But how does mollis mean that?