What does Professor Sherman say that makes the audience applaud for five minutes in The Twenty-One Balloons? Why does the crowd react that way?

In Chapter 3 of The Twenty-One Balloons, when Professor Sherman begins addressing the audience in the auditorium of the Western American Explorers' Club in San Francisco, he actually doesn't say very much to elicit five minutes of applause, but receives the applause simply because the crowd is excited about his experience.

He opens his address by saying how happy he is to be back home, which gets four minutes of applause. Next, he says, "I haven't been away very long, but I have certainly missed" before being interrupted by five more minutes of applause (38). The reason why this sentence excites the audience so much is because it reminds audience members that Professor Sherman has just traveled around the globe in the shortest amount of time possible for this time period.

The book is set in the late 1800s, soon after Jules Verne published his 1873 adventure novel, Around the World in 80 Days, based on growing beliefs about how fast one could travel the globe via railway lines. In fact, in 1870 the Erie Railway Company published statements, based on its train routes and times tables, predicting one could travel the globe in 77 days (The Kansas Tribute, 1870). In The Twenty-One Balloons, Professor Sherman started his voyage across the Pacific Ocean and was picked up in the Atlantic Ocean 40 days later, which means to Professor Sherman's audience that he had traveled around the world 40 days faster than what the acclaimed Jules Vernes predicted to be possible.