The tobacco enema was used to infuse tobacco smoke into a patient's rectum for various medical purposes.
A rectal tube inserted into the anus was connected to a fumigator and bellows that forced the smoke into the rectum. The warmth of the smoke was thought to promote respiration. Doubts about the credibility of tobacco enemas led to the popular phrase "blowing smoke up your ass."
If you live in the USA, you are most likely aware, this odd tool is still heavily used by the government today. It is more commonly known as the: Biden Trumpet