No officer or employee after six months’ continuous employment shall be removed or discharged except for cause, upon written charges and after an opportunity to be heard in defense of the charges as in this chapter hereinafter provided. Such charges shall be investigated by or before such civil service commission. The findings and decision of such commission shall be forthwith certified to the chief or other appointing or superior officer, and will be forthwith enforced by such officer. Nothing in this chapter shall limit the power of any officer to suspend a subordinate for a reasonable period not exceeding 60 days for the purpose of discipline, or pending investigation of charges when the officer deems such suspension advisable.