What is Laughing Gas

Uncle Albert's laughing gas is a symbol of unabashed joy, since it arises due to laughter and high spirits and causes one to float in the air. The symbolic elevation of one's person represents the elevation of one's spirits, and the fact that Jane and Michael become infected with laughing gas shows how youthfully joyous and carefree they truly are. In this sense, they are very similar to Uncle Albert who, despite his old age, retains those same qualities and is not ashamed of his inability to think of anything sad enough to bring him back down to Earth.