No, it's not really different from "higher wages" in the widest sense. Workers bargain, normally through their unions, over the conditions of sale of their ability to work. The amount they are paid is just one aspect of it; the other is the conditions under which it is exercised, including the length of time.There was another article on this in the June 1980 issued of the Socialist Standard entitled " A Shorter Working Week?" (unfortunately not yet included in the archives section but may soon be). It makes the additional point that a shorter working week cannot be a cure for unemployment, as some trade unionists and reformists have advocated.The Factory Acts, on the other hand, were reforms and had the wholehearted support of Marx who devoted a section of Volume 1 of Capital to the struggle for them. We've also always given them as an example of a reform that benefited the working class (we have never said that this is not possible).