Said tax collector, or any other tax collecting agency authorized by law for the collection of said taxes, shall pay over all moneys collected or to be collected as receipts from said two-mill tax to any trustee or successor thereto established as hereinafter in this chapter provided, and in the event that there is no such trustee, then said tax collector, or any other tax collecting agency authorized by law for collection of said taxes, shall pay over all such moneys into the county depository of each such county to the credit of a fund which shall be known as a "ferry fund." Any such moneys so paid into the county depository of each such county to the credit of said "ferry fund" may be expended at the direction of the ferry commission appointed for any county ferry. In no county within the terms of this chapter shall there be withheld from the state treasury under the provisions of this chapter and Sections 59-7-1 through 59-7-21, Mississippi Code of 1972, for any one year an amount in excess of the receipts from said two-mill tax. The provisions of this chapter shall be deemed to be a contract with the holders of any bonds or other obligations issued pursuant to this chapter.