The explorer of an uncharted land, like the discoverer of medical truths, dreams the dream of achievement and makes the dream reality. He moves on and on with curiosity, over craggy hill and desert waste. Every step is planned and measured critically, then at long last the goal is realized. It has been said that the explorer-scientist must put on his imagination as he would an overcoat when he speculates, and take it off like an overcoat when he sits down in the laboratory to test the hypothesis.
The explorer of the bronchial forest is inspired as he passes along the hospital corridor. No wonder, for there is a child struggling for breath, an older person plagued with hemoptysis and hard, racking cough. The cause might be a foreign body in the bronchus, a cancerous growth in the trachea. Who has made certain? Who has ventured beyond the larynx in