Section 56. Examination of books and accounts

The  mayor  shall  have
  authority at all times to examine the books and papers of  any  officer,
  employee  or department of the city and, as often as he may deem proper,
  to appoint one or more competent persons to examine, without notice, the
  accounts of any city officer or department, and  the  money,  securities
  and  property  belonging  to the city in the possession or charge of any
  officer or department and to report the result of such examination;  and
  he  may  administer  oaths to witnesses and take affidavits in all cases
  relating to the affairs of the city.