Describe the first face to face interaction of Mr.Otis and the ghost , when and why did he realize that he had been dogmatic in hi denial of existence of ghost?

Mrs. Otis like her husband was not frightened by the Ghost. Instead, when the Ghost gives the family a blood-curdling laugh, Mrs. Otis steps out of the bedroom wearing a light-blue dressing gown. She then explains to the Ghost that he must be suffering from indigestion, which his making him scream in such a manner. Like her husband, Mrs. Otis offers the Ghost, "a bottle of Dr. Dobell's tincture" to help cure his indigestion. The Ghost's indignation knows no bounds at the materialistic approach of the Otis family towards anything supernatural.