(d)On the completion of the parades, the prisoners shall be distributed into their respective gangs, and a responsible officer shall be placed in charge of each gang. The responsibility for the charge of a gang shall never be divided between two or more officers. The strength of a gang working outside the jail walls,-but within the jail precincts shall not, without the sanction of the Inspector-General, exceed 12 prisoners, there shall be atleast one head warder incharge assisted by another warder for every such gang. In the case of prisoners working inside jail walls, each gang may contain as many as can be conveniently and effectively supervised. Prisoners shall not be employed beyond the jail precincts without the special sanction of the Inspector-General in writing.