I bought this Goodyear sign on Saturday. It is porcelain and it was made in India. I believe it dates to 1900 or earlier. It states "Carriage Rubber "which was actually invented in the 1850s to use on carriage wheels. The manufacturers used "India Rubber" on the wheels so I am assuming this sign dates to pre 1900. Does anyone have any thoughts? I am also interested in the number "51" inside the bells. What does that stand for? Maybe I need to find an Indian tire historian?