Gutta-percha

Resin, pitch, sealing-wax, caoutchouc, sulphur, gutta-percha, and generally all bodies commonly termed resinous, besides a great variety of others, will be found to acquire, after friction, the power of attracting light bodies, and hence will be said, according to a limitation of terms already accepted, to be in an electrized or electrified state .

No player shall be allowed to wear projecting nails, iron plates, or gutta percha on the soles or heels of his boots.