Where did my thinking take the wrong turn

Hello,

Sorry for asking so much but I still have problems with the easy task of 
the 99 Ocaml problems.

I now have to revert a list.

I have this :

let reverse list =
     let rec reverse2 list2 acc =
         match list2 with
            | [] -> acc
            | x::xs -> reverse2 (x::acc) xs
     in reverse2 list [] ;;

But now list is never gets smaller so this runs forever.
I could take out the let rec reverse2 list acc part but somehow I have 
to make a place where rhe reversed string is stored.

Roelof