George Anderson, writing in 1852, described backward-skating figures, including the flying Mercury and the shamrock, as well as the Q figure, which became, in its various forms, an important part of the repertoire of skating movements for the rest of the 1800s. Anderson also described two combined figures, the salutation (already described by Jones) and the satellite. By the 1850s, the most important figures (eights, threes, and Qs) were developed, and formed the basis for figure skating at the time. In 1869, Henry Vandervell and T. Maxwell Witham from the London Skating Club wrote "System of Figure Skating", which described variations of the three turn (the only figure known before 1860), the bracket (first done on roller skates), the rocker, the Mohawk, the loop, the Q, and other figures. The Mohawk, a two-foot turn on the same circle, most likely originated in North America. Figure skating historian James Hines called grapevines, which was probably invented in Canada, "the most American of all figures". The Viennese style of figure skating, as described by Max Wirth's book in 1881, described connecting figures, which ultimately led to modern free skating programs.