No money shall be drawn from the State Treasury as salary or compensation to any officer or employee of the Legislature, or either branch thereof, except in cases where such salary or compensation has been fixed by a law in force prior to the election or appointment of such officer or employee; and the salary or compensation so fixed, shall neither be increased nor diminished so as to apply to any officer or employee of the Legislature, or either branch thereof at such Session; Provided, that this restriction shall not apply to the first session of the Legislature.