Terka Laona is working on the construction of Candeth Keep.

Don't mess with his Surveying Device or he will say.

Terka Laona tells you, "You destroyed my day's work! Now I have to go back and recalculate all of the distances! Get out of my sight, you bahka!"

You can only play with the Surveying Device can't pick it up.

Here are some green text that comes up when using the device:
You look through the spyglass and see the tumerok shamman drumming in front of a tree. Numbers seem to float by him and...
Ooops.
You shift the spyglass and it spins around, changing the numbers displayed on the wheel mechanisms.
You spin the spyglass around. It comes to rest in roughly the same position it started in, you think.
Ah, yes, this is obviously some sort of magical device. You press the little button near the base of the instrument.
With the locking mechanism released the spyglass spins freely.
The spyglass spins around and around. That was fun.