If the body of any deceased person be found buried on any lot or ground in the city, the owner or agent of which lot or ground cannot be found, it shall be lawful and is hereby made the duty of the director of public health of the city to cause such body to be disinterred and buried in a cemetery established by this chapter; provided, however, that the provisions of this section shall not apply to the remains of deceased persons which have been interred prior to the passage of this chapter. (Code 1941, Art. 15-7)