David Brooks invented the glass insulator in the early 1800s as a lightning deterrent for homes. Once the telegraph was invented, insulators were used to protect the wood poles from which the wires were suspended. Of course, electric lines and telephone lines also produced heat, and the wires were hotter than ever. Glass and porcelain insulators have become collector items that are admired for their shapes and colors. Corning Glass got into the business of producing insulators and are stamped with the brand Pyrex. The wood poles had cross arms with wood screws that the insulators were screwed onto. Porcelain insulators may have had metal screws embedded. The 1885 Depot Museum on Russell Street has an interesting collection of insulators and even a few spare ones for sale in the gift shop. The glass insulators are now used as paperweights and for window sill decorations instead of for protecting the wood poles. The telegraph keys exhibit at the Depot serve as a reminder that communication equipment has come a long way.