No corporation or person shall begin to operate or cause to be operated any vessel for the transportation of persons or property, for compensation, between points in this state, without first having obtained from the commission a certificate declaring that public convenience and necessity require such operation, but no such certificate shall be required as to termini between which any such corporation or person is lawfully operating vessels in good faith under this part as it existed prior to August 17, 1923, under tariffs and schedules of such corporations or persons, lawfully on file with the commission. Every applicant for such a certificate shall file in the office of the
commission application and evidence in the form required by the commission. The commission may, with or without hearing, issue the certificate as prayed for, or refuse to issue it, or issue it for the partial exercise only of the privilege sought, or issue it for operation between certain points only, and may attach to the exercise of the rights granted by the certificate such terms and conditions as, in its judgment, the public convenience and necessity require.