Read the passage carefully until you have got its main idea, and then select one appropriate word for each gap from the box following the passage. Despite the name, the Underground Railroad was not really a railroad, but was a network of people who assisted fugitive slaves. Many fugitives who escaped to the North and Canada received (1) along the way from individuals who were ( 2 ) in this network. By the early 19th century, the organization became so successful that it is ( 3 ) that between 1810 and 1850,100,000 slaves escaped from the South through the Underground Railroad. It was not a(n) ( 4 ) that it was called the Underground Railroad. Steam railroads had just ( 5 ) and the terms used to describe the people who helped and the fugitives were related to the railroad line. Fugitive slaves were called "parcels" and "passengers", the helpers were the "conductors", the people who provided their homes as refuge were called "stationmasters," and the homes were ( 6 ) to as "depots" or "stations". The route used was an important part of a successful escape. There were ( 7 ) secret routes that a conductor could use. The one used depended on where the search parties and slave catchers were ( 8 ) . Some trips required the use of many different routes. If it appeared that they might be in danger, a guide would change paths. Some guides and fugitives even hid out in bushes and swamps for many days until it was safe to continue on. Quickness was not the main (9) , instead safety was most important and as a result they often zigzagged in order to avoid (10). numerous capture accumulated assistance inspired estimated coincidence curiosity emerged concern referred stationed previous involved incident