Mr
Wilson's business is
small,'
explained Holmes. There was nothing
inside
his house to attract criminals. So I knew it must be
something
outside
the house. What could it be?
'Mr
Wilson told us that Vincent Spaulding - or John Clay
- spent many hours in the cellar. The cellar! He was doing
something in the cellar.
'I
asked more questions about Vincent Spaulding. I found
out that he was John Clay, one of London's most dangerous
criminals. What could John Clay want in Wilson's cellar? I could
think of only one answer. He must be digging a tunnel to another
building.
Then we visited Saxe-Coburg Square and I surprised you by
knocking on the pavement with my stick. I wanted to find out
exactly where the cellar was. I knew, from the sound my stick
made,
that there was no cellar in front of the house. Then I rang
the doorbell and Clay answered it. I saw that the knees of his
trousers were dirty. Clearly, he had been digging for many hours.