Now everybody in the family was interested. Mr Otis started to think that maybe there were ghosts after all. Mrs Otis said that she wanted to join a club of people who were interested in ghosts, and Washington wrote a long letter to a detective agency about how difficult it was to remove blood stains that were connected with crimes.

Then, that night something happened which made them all completely certain that ghosts existed. It had been a warm and sunny day, and in the cool of the evening, the whole family went out of the house. They did not come home till nine o'clock, and then they had a small meal.

They did not talk about ghosts. Sometimes, people see ghosts because they have been talking about ghosts, and they are expecting to see something. But this was not true about the Otis family that evening.

Mr Otis told me later that the things that they talked about were ordinary things. The sort of things that you might expect from Americans who have travelled and been well educated. For instance, they discussed the fact that the American actress Miss Fanny Davenport was so much better than Sara Bernhardt, the English actress.

They talked about how difficult it was to get their favourite foods - green corn, buckwheat cakes, and hominy - even in the best English houses.

They discussed why the city of Boston made the world a better place; why railway travel was done much better in the United States; and why the New York accent sounded so much nicer than the London one.