largest and wealthiest, London was quite 4. the capital of the world. The city was growing 5. and its transport became a big issue. People tried to find the solution to the problem within the innovations of the 6. Revolution. The Metropolitan railway opened and was at once adopted by 7. as a 8. way to travel. People began to call the new system "the Underground", or more 9. "The Tube", a 10. tube-like tunnels that characterize the older parts of the network.

largest and wealthiest, London was quite 4. literally the capital of the world. The city was growing 5. rapidly and its transport became a big issue. People tried to find the solution to the problem within the innovations of the 6. industrial Revolution. The Metropolitan railway opened and was at once adopted by 7. Londoners as a 8. fashionable way to travel. People began to call the new system "the Underground", or more 9. affectionately "The Tube", a 10. reference to the narrow tube-like tunnels that characterize the older parts of the network.