During the peak years of steamboating, the Mississippi and Ohio Rivers carried more than 11,000 paddle wheelers. For this fare, a bargain by today's standards, the passenger was provided with transportation, meals and lodging on an impressive boat with excellent accommodations. The Port of Cincinnati was a principal center of Ohio River steamboat operations in the 1850s. Steamboat arrivals and departures in Cincinnati averaged more than 20 per day. The steamboat era has touched the lives of all Americans in such interesting ways such as contributing to common vocabulary.
Many current phrases come from the steamboating era such as letting off steam and fiddlin' around.
The huge paddlewheels were driven by steam. Since pressure inside the steam boiler rose to extreme levels at times it was relieved through a check valve. Relieving that pressure was naturally called letting off steam and it came to describe the human emotion of ridding tension. Some people carried fiddles with them, playing along the riverbanks and wharfs for pennies. During this period in time if you didn't work, you were said to be fiddlin' around.