Section 13-538. Fund for current needs

For  the  purpose  of  meeting
  disbursements                       for                        pensions,
  pensions-providing-for-increased-take-home-pay,   annuities   and  other
  payments in excess of the receipts, there may be kept an available fund,
  not exceeding ten per cent of the total  amount  in  the  several  funds
  provided  for  by  this  chapter,  on deposit in any bank in this state,
  organized under the laws thereof or under the laws of the United States,
  or with any trust  company  incorporated  by  any  law  of  this  state,
  provided  such bank or trust company shall furnish adequate security for
  such funds and provided that the sum so deposited in  any  one  bank  or
  trust  company  shall  not  exceed  twenty-five  per cent of the paid-up
  capital and surplus of such bank or trust company.