Looping CreateEmptyMovieClip not working

programming flash
1

I have the code below which should loop and createemptymovieclips, however it does loop with no errors but the movieclips don’t get created. I know they don’t get created because I can’t do a loadmovie, however if I try to manually create these (ie, a new line for each createempty, it does work).

for(X=0;X<=39;X++){
idepth = X + 130;
eval("z_Brickmc_"+X+" = this.createEmptyMovieClip(\"zBrick"+X+"_mc\","+idepth+");");
}