What name is this?

As I've mentioned, a lot of stuff was left behind by the previous owner when we bought our house. One item was the Calder-esque mobile that hangs in the living room. Even though it's in a bit of a weird spot, I've always liked it there and we never moved it.

I'd like to know more about it though. It is signed by the artist, and although I can see that the date is 1957 and the first letter may be J, I can't for the life of me figure out the rest of the name. I've searched online for various names that it could be, but nothing comes up.

So I'm asking that you take a look at the signature and tell me what you see. And if you actually know anything about these kinds of mobiles, please share!

Thanks, gang.