Peter Potamus
Peter Potamus is a cartoon made by Hanna-Barbera.  It was first shown on television on September 16, 1964. The main characters are a friendly purple hippopotamus called Peter Potamus and his friend So-So the monkey.  Together they explore the world in a time-traveling hot-air balloon.  Peter has a special "Hippo Hurricane Holler" that helps him blow away his enemies.