Section 2. All persons desiring authority to perform the duties of an engineer shall apply to the boiler inspector of such cities, who shall examine the applicant as to his knowledge of steam machinery and his experience in operating the same, also the proofs he produces in support of his claim, and if, upon full consideration, the inspector is satisfied that the applicant's character, habits of life, knowledge and experience in the duties of an engineer, are all such as to authorize the belief that he is a suitable and safe person to be entrusted with the powers and duties of such a station, he shall grant him a license, upon the payment of three (3) dollars, authorizing him to be employed in such duties for the term of one year, and such license shall be annually renewed, without examination, upon the payment of one (1) dollar, provided it is presented for renewal within ten days after its expiration. Licenses so granted shall be graded into two classes: One of which shall entitle the licensee to have charge of or to operate stationary steam-boilers and steam-engines only; the other of which shall entitle the licensee to have charge of or to operate portable steam-boilers and steam-engines only; such licenses shall not be transferred from one grade to the other without a re- examination, said re-examination to be conducted without cost to the licensee.
No person shall be eligible to examination for a license unless he furnishes proof that he has been employed about a steam-boiler or steam-engine for a period of not less than two years, prior to the date of application, which must be certified to by at least one employer and two licensed engineers.