law: Marine Insurance Act, 1963 
  73. General average contributions and salvage charges 
  (1) Subject to any
  
  express provision in the policy, where the assured has paid, or is liable for,
  
  any general average contribution, the measure of indemnity is the full amount
  
  of such contribution if the subject-matter liable to contribution is insured
  
  for its full contributory value; but, if such subject-matter be not insured for
  
  its full contributory value, or if only part of it be insured, the indemnity
  
  payable by the insurer must be reduced in proportion to the under-insurance,
  
  and where there has been a particular average loss which constitutes a
  
  deduction from the contributory value, and for which the insurer is liable,
  
  that amount must be deducted from the insured value in order to ascertain what
  
  the insurer is liable to contribute.
  (2) Where the insurer
  
  is liable for salvage charges the extent of his liabilities must be determined
  
  on the like principle.