A top racehorse was brought down at Royal Ascot with a shot from a high－tech sound gun， a court was told yesterday． The gun was built into a pair of binoculars and fired from the crowd as the horse was （1） ______ sight of certain victory． The “technically brilliant” ultra－sonic device－（2） ______ could not be heard by people－was devised by a back－street inventor． It was to be used with potentially devastating effect in a secret plan “to destroy the entire system of race－course betting and bookmaking in this country，” defence lawyer Jonathan Goldberg told Southwark Crown Court in London． He said it had the potential to make a fortune in bets （3） ______ the favourite because it made sure that the horse would lose． It was used last year to unseat the leading jockey Greville Starkey from Ile de Chypre just before the end of the King George V Handicap， which it （4） ______ （doubt） would have won， he said． The astonishing story was told by the defence during a trial in which the inventor of the （5） g______， James Laming， denies drug conspiracy charges． It came to light because of his alleged connections with a drug baron who wanted to use the gun to help him win large bets． The inventor is a 49－year－old grandfather and south London car dealer who lives with his mother－in－law in a terraced house． He told the court that he got all the （6） inf______ on ultra－sonics for the gun from the Encyclopedia Britannica and tested it on horses in fields． The gun was made from a pair of race binoculars． Showing them to the jury， Mr Goldberg said： “This device subjected a passing racehorse to a sudden and （7） ______ （deaf） noise which we human beings cannot hear at all． It is the equivalent in suddenness to letting a loud firework （8） exp ______ in its ears．” The noise would be “a horrible ear－piercing shriek” like the feedback from a microphone． Because racehorses were sensitive and temperamental it would have the （9） ef ______ of making the horse swerve and unseat the rider． “It left no evidence of its use and no permanent disability for the animal，” he said． The plan was to use the gun for horse races and possibly for greyhound races． Mr Goldberg said： “He would fire it （10） ______ the favourite or second favourite in a race．”“These criminals， of course， were in a unique position to ensure that the horse lost．”