In addition to convicts sentenced to imprisonment in the county jail, the jail is used as a prison for the safekeeping or confinement of the following persons:
(1) Persons committed for trial for public offenses;
(2) Convicts sentenced to imprisonment in the penitentiary, until their removal thereto;
(3) Persons committed for contempt or on civil process;
(4) Persons committed on failure to give security for their appearance as witnesses in any criminal case;
(5) Persons charged with, or convicted of, a criminal offense against the United States;
(6) Insane persons, pending transfer to a mental hospital or other disposition; and
(7) All other persons committed thereto by authority of law.