[jQuery] .eq(variable) strange behaviour

[antoinepairet]

Hi!
 I'm trying to have a menu for which each item loads after the
 preceding one is loaded. For this purpose, I wrote the following
 function:

 function menuLoading(currentMenuItem,menuLength){
    console.log(currentMenuItem);
    currentMenuItem++;

    if(currentMenuItem<=menuLength){
        $('.menu li').eq(currentMenuItem).animate({"opacity" : 1},
 3000).animate({"opacity" : 0.6}, 2000 ,menuLoading
 (currentMenuItem,menuLength));
        }
    }

 Initially, the li items of the menu are set at opacity 0. With the
 function I modify the opacity. I'd like every item to start loading
 when the previous one is shown. However, all the elements appear at
 the same time. If I replace eq(currentMenuItem) by eq(1), only the
 first is shown.

 How could I make it?

 Thanks a lot!

ps: $('.menu li:eq(' + currentMenuItem + ')').animate({"opacity" : 1},
3000).animate({"opacity" : 0.6}, 2000 ,menuLoading
(currentMenuItem,menuLength)); works like the code above bu does not
do what is expected