SideScrolling?

okay, thanks to a previous post on the forums I have this, which works great to scroll my text up and down. but I’f I want to apply it to something that I want to scroll left and right, what do i do? is it just a different command in the textwindow.scroll? if so what is it/where can I find out ?
so i have this right now:

up.onPress = function() {
_root.onEnterFrame = function() {
textwindow.scroll –
}
}
up.onRelease = function() {
delete _root.onEnterFrame
}

/************************************/
dn.onPress = function() {
_root.onEnterFrame = function() {
textwindow.scroll ++
}
}
dn.onRelease = function() {
delete _root.onEnterFrame
}