What is it? Game 70

Hooray! It's time for our collaboration with the What is it? blog - can you guess what this strange contraption is for?

Place your guess in the comment section - no prize this week, so you're playing for fame and glory only. For more clues (and more guessing fun), check out the What is it? blog.

A trap for taking live animals, the top and bottom both collapse, making the height just a couple of inches. It's placed in a shallow stream, when it's tripped the animal's leg is caught, after the top expands the leg is released and the elevation apparatus is activated, raising the trap several inches above the water. It's called a Gibbs Armadillo trap because of how it looks, but it was used for catching live muskrats so they could be transported to another area, patent number 1,765,144.