Vienna valve trombones use Vienna Valves which were one of the earliest valve systems used in wind instruments. These valves were first publicly reported in 1815 and valved trombones were first introduced in the late 1830s.
History
The Vienna valve was invented in Leipzig in 1821 by Sattler, predating the Perinet valve and rotary valve used in France and Germany (and in all French horns). The Vienna Valves (or Double Valves) have two short parallel pistons connected at the bottom by a bar that is moved by a long rod or linkage connected to the spring-loaded finger plate. The Vienna system was in common use in Germany on all kinds of instruments including trumpets up to 1850. Adolph Sax invented instruments with 6 independent valves 3 for each hand, but only the most dexterous musicians were able to play them.
The valve trombone has definite advantages over the more common slide trombone, such as taking up less room in a seated orchestra. Verdi, for example, composed passages that would have been impossible on a normal slide trombone.