fly rod eyes

Question
I have seen old rods with simple rings attached for eyes and was wondering when the change from these simple rings to the more standard snake eyes of today came about. Knowing this would be helpful in dating old rods. Thanks.

Answer
Marlon,
First let me lead you to the most commonly used idiom , which is not eyes but guides.
I always assumed snake guides were put into production with the later industrial revolution or so. In the  later 19th century machines were making snake guides.  
I don't think you can put an exact date on all bamboo rods as to their type of components. Some makers kept old guides for years and used them.
For example , in AJ Campbell's book, Classic %26 Antique Fly-Fishing Tackle: A Guide for Collectors %26 Anglers, he describes the history of the Edwards various rod maker family as adopting snakes around 1896. Orvis rods much earlier .
It's an interesting questions with several answers.
Good Luck,
Mac

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