In case the office of city clerk shall become vacant from any cause the mayor and aldermen shall forthwith appoint a clerk pro tempore, who shall hold the office and perform the duties until a clerk shall be elected by the city councils at a convention which may be held at any time for that purpose.
RSA 48:8
GS 43:6. GL 47:6. PS 49:7. PL 53 :7. RL 65:7.