How is the sequence of animals in the stone room on Riven supposed to be found?

Question

To get into the Age of Tay, you have to solve the puzzle of the room with a circle of stones by pushing down in the correct order the stones bearing the image of certain animals, specifically these (spoilers!):

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<sub>(source: mystjourney.com)

(source: mystjourney.com)

(source: mystjourney.com)

(source: mystjourney.com)</sub>

(Source for pictures.) I know these are connected to the spherical rollers scattered around the Jungle Island - each roller has a number and a sound. I can understand the connection of the last four sounds to their animals, but the #1 roller (in the office) just makes a scraping sound. I guess the picture isn't filled out like most of them are, so the animal could be gutted, hence the scraping (like with a knife)? That seems like a very tenuous connection.

What am I missing? How was I supposed to solve that puzzle?

Answer 1

Not only do they make sounds, but the spheres are also embedded in representations of the animals, with the sphere forming the eye.

To find out what #1 is, you have to find out from which animal the sphere has been removed.

It's underwater

and

It's mentioned in Ghenn's journal

Answer 2

In Ghen's journal in the lab, he mentions finding a weird object anchored in the water, and he gets it retrieved (thus the orb on the desk). The next passage says it reappears the next day (either replaced by natives/catherine's spies, or Atrus writing from the outside? doesnt matter).

When you get the lake near the village (the one with the sub) if you look around, you can spot the orb in the water

I'm not sure if it was before or after the lake, you find one of the spying chairs, and you can rotate it to look around that lake, finding landmarks like the village and the sacrifice cone. If you line up land marks, and point the viewer at where the orb is, you will notice there is an outline on the rock, which when reflected into the water's surface, is the shape of the fish.

If you leave it pointed at the fish, and head back to the lake, you will notice the spying device (The dalek looking thing in the water) will be pointed near where the orb is, thus associating the "fish" with the desk/reappearing/silent orb.