258. Payment of rent by post.

Ordinarily, if rent is sent by post, this is at the tenant's risk if the rent is not received. If, however, the landlord has expressly or impliedly authorised that method of payment then, as the postal operator transmits the letter as the landlord's agent in such circumstances, the landlord assumes the risk1, and payment is then deemed to be made at the date of posting2; but the tenant must exercise due care in addressing and posting the rent3. The agreement of the landlord that he will accept substituted performance of the tenant's obligation to pay the rent in cash