Sec. 2. From and after the passage of this Act, in all counties of the State of Texas which have a population of not less than eighty-three thousand (83,000) and not more than eighty-four thousand (84,000); and in all those counties of the State of Texas which have a population of not less than twenty thousand, five hundred and sixty (20,560) and not more than twenty thousand, five hundred and seventy (20,570); and in all those counties of the State of Texas which have a population of not less than twenty thousand, two hundred and thirty (20,230) and not more than twenty thousand, two hundred and fifty (20,250); and in all those counties of the State of Texas which have a population of not less than thirteen thousand, three hundred and twelve (13,312) and not more than thirteen thousand, three hundred and fifteen (13,315); and in all those counties of the State of Texas which have a population of not less than thirteen thousand, two hundred and thirty (13,230) and not more than thirteen thousand, two hundred and thirty-five (13,235), according to the last preceding Federal Census, the amount which shall be allowed for office and travel expenditures for the County Superintendent of Public Instruction shall be Six Hundred Dollars ($600) per annum.