13.(1) Cantonments shall be divided into three classes, namely:- (i) Class I Cantonments, in which the civil population exceeds ten thousand; (ii) Class II Cantonment, in which the civil population exceeds two thousand five hundred, but does not exceed ten thousand; and (iii) Class III Cantonments, in which the civil population does not exceed two thousand five hundred. (2) For the purposes of sub-section (1), the civil population shall be calculated in accordance with the latest official census, or, if the Government, by general or special order, so directs, in accordance with a special census taken for the purpose.