Section 1. The salary of the Superintendent of Public Instruction in each county in Texas having a population of not less than ten thousand, three hundred and sixty (10,360) and not more than ten thousand, three hundred and eighty (10,380), and in each county having a population of not less than ten thousand, three hundred and ninety-nine (10,399) and not more than ten thousand, four hundred and ninety-nine (10,499) inhabitants, according to the last preceding Federal Census, shall from and after the passage of this Act be Twenty-four Hundred Dollars ($2400) per annum.