The banner bears the character ling (order). For an example with the same character, see Helen White, Snuff Bottles from China, The Victoria and Albert Museum Collection, London, 1992, pp. 58-59, pl. 22.
For another bottle of similar type depicting a Manchu bannerman galloping at speed, see Hugh M. Moss, Chinese Snuff Bottles of the Silica or Quartz Group, London, 1971, p. 52, no. 133, where the author notes that the Manchu army was split into eight banners, each of a distinct colour or combination of colours and a bannerman was a member of any of these.
For another example originally from the Monimar Collection, see Rachelle R. Holden, Rivers and Mountains Far from the World, New York, 1994, p. 340-341, no. 152