The old writing can be found by inserting 100 numulites into one of the stone chests inside the House on the Hill on Fossil Island. There is a chance nothing will happen or a spike shooting out and stabbing the player for 9 damage, wasting the numulites.
This note can be added into the Fossil island note book.
For an exhaustive list of all known sources for this item, see here
I believe my presence here is causing unrest in the creatures. Whilst at first they kept distance, they are beginning to display violently towards me, no doubt linked to the growing conflicts between their tribes. Perhaps I am a trophy to prove dominance? Nevertheless, they are not yet evolved to penetrate my skin.