Spinnaker booms and multiple jibs are rarely seen. The city's history is a continuous alternation between economic booms and recessions. This industry flourished for nearly two centuries, albeit with periodic booms and slumps. Traditionally booms, and other spars, were made of wood. Pine lumbering persisted with periodic booms and busts through the 1960s. The concept makes use of floating booms that divert rather than catch the debris. These nets were projected from the sides of the ship on wooden booms. They were later collected downstream by systems of nets and booms. Each man goes through booms and busts. Banking can be pro-cyclical by contributing to booms and busts. After detection of the leak, booms and vacuum trucks were deployed. With all of its instrument booms and antennae deployed, its dimensions are . This was done with the placement of skimmers and booms. Downtown had short skyscraper-building booms beginning in the 1970s. This led to several booms and busts related to tobacco.