Visualize the structure next to Gulliver's ear. What is it like and why was it built?

In my opinion, the structure would be similar to a scaffold. Tall, off the ground, and with enough room for the gathering of a few men. Tall enough for those on the scaffold to attempt to communicate with Gulliver safely.

I saw a stage erected about a foot and a half from the ground, capable of holding four of the inhabitants, with two or three ladders to mount it: from whence one of them, who seemed to be a person of quality, made me a long speech, whereof I understood not one syllable.