§ 3. Measurement and numbering; tonnage tax
The Commissioner of Customs shall be charged with the supervision of the laws relating to the admeasurement of vessels, and the assigning of signal letters thereto, and of designating their official number; and on all questions of interpretation growing out of the execution of the laws relating to these subjects, and relating to the collection of tonnage tax, and to the refund of such tax when collected erroneously or illegally, his decision shall be final.