When an agent does more than he
is authorized to do, and when the part of what he does, which is within his authority, can be separated
from the part which is beyond his authority, so much only of what he does as is within his authority is
binding as between him and his principal.
Illustration
A, being owner of a ship and cargo, authorizes B to procure an insurance for 4,000 rupees on the ship. B procures a policy
for 4,000 rupees on the ship, and another for the like sum on the cargo. A is bound to pay the premium for the policy on the ship,
but not the premium for the policy on the cargo.