law: Negotiable Instruments Act, 1881 
  89. Payment of instrument on which alteration is not
  
  apparent 
  Where a promissory note, bill of exchange or cheque has been
  
  materially altered but does not appear to have been so altered, or where a cheque
  
  is presented for payment which does not at the time of presentation appear to
  
  be crossed or to have had a crossing which has been obliterated, payment
  
  thereof by a person or banker liable to pay, and paying the same according to
  
  the apparent tenor thereof at the time of payment and otherwise in due course,
  
  shall discharge such a person or banker from all liability thereon, and such
  
  payment shall not be questioned by reason of the instrument having been
  
  altered, or the cheque crossed.