The Semmering railway

It is used as a word picture to show Frances that she needs to have faith. The railway was built before there was even a train that could make the trip...the people of the Alps had faith that someday, the train would come. Frances was second-guessing her choice to buy the house she bought for the life she said she didn't even have. The realtor was trying to give her hope that one day, there might be a wedding in the house and a family to fill the rooms. Hope that explains things! :-)