law: Marine Insurance Act, 1963 
  44. Implied condition as to commencement of risk 
  (1) Where the
  
  subject-matter is insured by a voyage policy "at and from" or
  
  "from" a particular place, it is not necessary that the ship should
  
  be at that place when the contract is concluded, but there is an implied
  
  condition that the adventure shall be commenced within a reasonable time, and
  
  that if the adventure be not so commenced the insurer may avoid the contract.
  (2) The implied
  
  condition may be negative by showing that the delay was caused by circumstances
  
  known to the insurer before the contract was concluded, or by showing that he
  
  waived the condition.