Do you have a container of old glue that has dried out and hardened? It may be useless to you, but depending on its chemical composition, it could spell trouble if thrown into the trash. Even in a hardened state, solvent-based glues are very flammable and should never be tossed in the trash. Instead, dispose of them with your household hazardous waste at a designated collection site. If the old glue is water-based and hardened, you can safely throw it away in your regular trash.
ANDREWS MCMEEL SYNDICATION