All emergency expenditures shall be paid for by the issuance of emergency warrants which shall be paid from any moneys on hand in the county treasury in the fund properly chargeable therewith and the county treasurer shall pay such warrants out of any moneys in the treasury in such fund. If at any time there are insufficient moneys on hand in the treasury to pay any of such warrants, they shall be registered, bear interest and be called in the manner provided by law for other county warrants.