Because the day is Friday and the date is the thirteenth the Thirteen Club ( an organisation which exists for the purpose of defying superstition ) met for their luncheon in the Savoy Hotel in London - at the luncheon which is only held when the thirteenth day of the month is a Friday the members of the Club do everything they can to flout time-honoured superstitions - they spill salt , walk under ladders and open umbrellas indoors - photo shows members of the Thirteen Club at luncheon under opened umbrellas April 13th 1934