| (a) | - | A buys goods from B, knowing that he is an agent for their sale, but not knowing who is the principal. B's principal is the person entitled to claim from A the price of the goods, and A cannot, in a suit by the principal, set-off against that claim a debt due to himself from B. |
| (b) | - | A, being B's agent; with authority to receive money on his behalf, receives from C, a sum of money due to B. C is discharged of his obligation to pay the sum in question to B. |