| (a) | - | A owes B, among other debts, 1,000 rupees upon a promissory note, which falls due on the first June. He owes B no other debt of the amount. On the first June, A pays to B 1,000 rupees. The payment is to be applied to the discharge of the promissory note. |
| (b) | - | A owes to B, among other debts, the sum of 567 rupees. B writes to A and demands payment of this sum. A sends to B 567 rupees. This payment is to be applied to the discharge of the debt of which B had demanded payment. |