To lend out, [F5to inhabitants of the area of the authority] the books of any library under their control, or such of them as they may consider proper; and at their discretion to grant the same privilege to the inmates of industrial schools, training ships, reformatories, barracks, and other similar institutions established for or in the [F5area]; and also to any person carrying on business within the limits of the [F5area], or to any employee engaged in employment therein, although such person or employee . . . F6 may not reside within such limits: