Derailleur gears designed and built in the late 19th century. One example is the Protean two-speed derailleur available on the Whippet safety bicycle. The French bicycle tourist, writer and cycling promoter Paul de Vivie (1853–1930), who wrote under the name "Vélocio", invented a two speed rear derailleur in 1905 which he used on forays into the Alps. Some early designs used rods to move the chain onto various gears. 1928 saw the introduction of the "Super Champion Gear" (or "Osgear") from the company founded by champion cyclist Oscar Egg, as well as the Vittoria Margherita; both employed chainstay mounted 'paddles' and single
Word sort have a responsibility to students they serve to identify their needs and implement instructional strategies to scaffold students’ understandings of sounds. Intervention strategies may be necessary in remediating students who cannot correctly identify sounds in isolation on a given opportunity. Programs like Reading Recovery have contemporary phonemic techniques embedded in the program. Also, books and poems may specifically focus on word families and similar sound patterns for children to identify and understand in context. Sound sorts can be integrated through programs, or very inexpensively through teacher-created materials. For example, students can sort pictures by beginning sound, rhyme, or ending sound.