Is this an original early Sheave bearing??

[Tiefel]

Hi all! New to this group and I'm hungry to learn about the history of sailing ships.. I found this on a beach in the Caribbean, was originally a complete green color probably do to the copper content within everything..  I was wondering if this is an actual sheave bearing? All brass on the outer and bronze bearings in the center. Looks to be hand made originally with the non-concentric bronze needle sleeves. Let me know your thoughts and if so what time period.. Also maybe a link to the history on such early linear bearings? Also what the heck is this bronze/brass ball piece might have been to? It has a small hinge fold on the underside..  Thanks! 

[wefalck]

Blocks with roller bearings appear in the later 19th century literature. When they have metal sheaves, they are usually meant for wire ropes.

[Tiefel]

Hey thanks for responding my friend! I actually found out that they go back even earlier, how early is a tough question... I found a guy that collects blocks and rebuilds them.. He explained that the first ones were bronze and brass like the one I posted.. then they became steel . This one had a wooden body to it that obviously rotted away... I'm trying to still find which country most likely made this design. Many designs have the linear bearings attached to a center arm instead of them being attacked to 2 outer discs... It's going to take more time... 

[druxey]

Definitely a crude roller bearing. However, the ball does not make sense for a block.