cables were cast off, and the boy called
out,----

"START--ER-R-R!"

The steamer then began to glide away from the landing again, and was
soon swiftly shooting over the water towards one of the arches of the
next bridge up the stream.

"Now," said Rollo, "how are they going to get this tall smokepipe
through that bridge?"

"You will see," said Mr. George.

Rollo looked up to the top of the smokepipe, which seemed to be
considerably higher than the crown of the arch that the steamer was
approaching. How it could possibly pass was a mystery. The mystery was,
however, soon solved; for, at the instant that the bows of the steamer
entered under the arch, two men, taking hold of levers below, turned the
whole smokepipe back, by means of a hinge joint that had been made in
it, not far from the deck. The hinge was in the back side of the
smokepipe, and of course in bending the pipe back there was an opening
made in front; and through this opening the smoke, while the steamer was
passing through the bridge, came out in dense volumes. As soon, however,
as the arch was cleared, the pipe was brought back into its place again
by the force of great weights placed at the ends of the levers as a
counterpoise. Thus the opening below was closed, and the smoke came out
of the top of the pipe as before.

[Illustration: SHOOTING THE BRIDGE.]

As soon as the boat had passed the bridge, Rollo, looking forward, saw
another landing at a short distance in advance of them.

"Here comes another landing," said Rollo. "Is this the Westminster
landing, do you think?"

"No," said Mr. George.

"How do you know?" asked Rollo.

"We have not come far enough yet for the Westminster landing," said Mr.
George.

"How shall you know when we get there?" asked Rollo.

"I shall inquire," said Mr. George. "Besides, the Westminster landing
must be at Westminster Bridge, and Westminster Bridge is above
Hungerford Bridge; and I shall know Hungerford Bridge when I see it, for
it is an iron suspension bridge, without arches. It is straight and
slender, being supported from above by monstrous chains; and it is very
narrow, being only intended for foot passengers."

"Well," said Rollo, "I will look out for it."

"I meant to have asked you," said Mr. George, "while we were on London
Bridge, whether it would be best for us to take lodgings in the city or
at the West End. Which do you think?"

"I don't know," said Rollo. "Which do you think would be be