Tic-tac is the secret and complex sign language used by bookmakers at racecourses to indicate movements in the price of a horse.
Those plying this skill usually wear white gloves and stand on wooden crates so they can be easily seen, although mobile phones have made the art a rarer sight.
The signs are further encoded by use of the 'twist card' which jumbles the racecard numbers for use by specific firms.
Most prices are also known by slang, as in the case of Burlington Bertie 100-30. Or scruffy and dirty, one hundred to thirty.
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.