An inland 1[mechanically propelled vessel] having engines of 10[forty] or more nominal horse-power, but of less than 6[one hundred] nominal horse-power, shall not proceed on any voyage unless she has—
(a)as her master a person possessing a second-class master‟s certificate granted under this Act, or any certificate referred to in clause (a) of section 25, and
(b)as her engineer a person possessing a first-class engine-driver‟s certificate granted under this Act, or an engine-driver‟s 7[certificate granted or deemed to be granted under the Merchant Shipping Act, 1958 (44 of 1958)] or any certificate referred to in clause (b) of section 25:
Provided that a 1[mechanically propelled vessel] shall be deemed to have complied with this section if she has as her master and engineer a person possessing both a certificate referred to in clause (a), and a certificate referred to in clause (b), of this section.