The Rates levied under the Authority of this Act shall be applied, first, in paying and discharging the Debts and Obligations contracted by the Commissioners and Overseers acting under the recited Acts, and due and subsisting at the Time of the passing of this Act; secondly, in paying the Costs of obtaining and passing this Act, and incidental thereto: and, lastly, in paying and defraying Salaries and Allowances to the Clerk, Treasurer, Collectors, Superintendent, Water Bailiffs, and other Officers, and other Expenses incurred in carrying this Act into execution.