A travelling clock, normally with a cylinder form of lever escapement mounted on a separate platform, developed in France in the early 19th century and made in great numbers in that country in the later 19th and early 20th centuries. The form began to evolve at the end of the 18th century, the fashion led by Abraham-Louis Breguet who produced small square clocks with glass sides owing something to the shape of pendules d'officier or Capucines, but most perhaps to the four-glass clocks or small r間ulateurs. The general form remained constant, though thousands of variations were made in details of panels and frames - or in size, which might vary in height from 2 or 3 in. To 12 in.