7.(1) No contract for sea-insurance ¹[* * *] shall be valid unless the same is expressed in a sea-policy. (2) No sea-policy made for time shall be made for any time exceeding twelve months. (3) No sea-policy shall be valid unless it specifies the particular risk or adventure, or the time, for which it is made, the names of the subscribers or underwriters, and the amount or amounts insured. (4) Where any sea-insurance is made for or upon a voyage and also for time, or to extend to or cover any time beyond thirty days after the ship shall have arrived at her destination and been there moored at anchor, the policy shall be charged with duty as a policy for or upon a voyage, and also with duty as a policy for time.