in w3school (try it) I have this code:

```
<!DOCTYPE html>
<html>
<body>

<img name="slide" class="slider" src="" width="400"/>

<script>
var i = 0;
var path = new Array();
path[0] = "http://vignette2.wikia.nocookie.net/batman/images/9/92/Batman-ArkhamKnight-BatsuitRender.png/revision/latest?cb=20140605151444";
path[1] = "http://vignette4.wikia.nocookie.net/injusticegodsamongus/images/c/c5/BATGIRL.png/revision/latest?cb=20130527034044";
path[2] = "http://vignette2.wikia.nocookie.net/injusticegodsamongus/images/b/bb/Raven_Render.png/revision/latest?cb=20130318184222";
path[3] = "http://vignette1.wikia.nocookie.net/injusticegodsamongus/images/7/7f/ARES.png/revision/latest?cb=20130411230035";

function swapImage() {
    document.slide.src = path[i];

    if (i < path.length - 1)
        i++;
    else 
        i = 0;

    setTimeout("swapImage()", 2000);
}

window.onload = swapImage;

</script>

</body>
</html>

```

So I am trying to use `setTimeout` function and it works, but is it possible to change these images slow() ?