"Do you see any reason," continued Mr. George, "why they should place the Tower at
the lower end, rather than at the upper end, of the city?"
"No," said Rollo, "I do not see any reason in particular."
"The reason was," said Mr. George, "that what they had reason to guard the city against was the danger of an attack from enemies coming up the river in ships from the sea; and so they placed the Tower below the city, in order to intercept them. But now the city has spread and extended down the river far below the Tower, and back far beyond the old wall; so that the Tower is, at the present time, in the midst of an immense region of streets and warehouses, and it is no longer of any use as a fortification. It is too high up."
"What do they use it for, then?" said Rollo.
"It is used by the government," said Mr. George, "as a sort of strong box, to keep curiosities, treasures, and valuables of all sorts in, and any thing else, in fact, which they wish to have in safe and secure custody. They keep what are called state prisoners there."
"Can we go in the Tower," said Rollo, "and see all these things?"
"Yes," said Mr. George, "we can see the treasures and curiosities; but I believe there are no prisoners there now."
Just then Rollo heard a rapping sound upon the stone of the sidewalk near him. He looked round to see what it was. There was a blind man coming along. He had a stick in his hand, which seemed to be armed at the lower end with a little ferule of iron. With this iron the blind man kept up a continual rapping on the flagstones as he slowly advanced. The iron produced a sharp and ringing sound, which easily made itself heard above the thundering din of the carriages and vans that were rolling incessantly over the bridge, and served as a warning to the foot passengers on the sidewalk that a blind man was coming. Every one hearing this rapping looked up to see what it meant; and, perceiving that it was a blind man, they moved to one side and the other to make way for him. Thus, though the sidewalk was so crowded that a person with eyes could scarcely get along, the blind man, though he moved very slowly, had always vacant space before him, and advanced without any difficulty or danger.[B]