"Sec. 2187. Compensation of vice-mayor and councilors � Full pay for sick mayor. � The municipal council may grant to the vice-mayor and each councilor a per diem not to exceed ten pesos in the municipalities of the first class; eight pesos in municipalities of the second class; six pesos in municipalities of the third class; and four pesos in the fourth and fifth class municipalities, for each day of regular or special session of the council actually attended by them: Provided, however, That no per diems may be granted for more than four special sessions a month. When, by reason of absence, suspension, or other disability, the mayor ceases to discharge the duties of his office, the vice-mayor or councilor acting as mayor shall receive compensation equivalent to the salary of the mayor during the period of such service."