Gargoyles are thought to protect churches from evil spirits and demons. Their wide open mouths are said to symbolize devouring giants. Some legends say that gargoyles come to life at night or when the wind or rain passes through their mouths. According to French legend, Saint Romanus saved his country from a dragon by mounting its head on the wall of a church. Gargoyles were originally used as waterspouts to shed rainwater from buildings, but their use declined in the early 18th century.