<div id="slideshow1" class="slide"><div>frame 1div></div>
<div id="slideshow2" class="slide" style="display: none"><div>frame 2div></div>
<div id="slideshow3" class="slide" style="display: none"><div>frame 3div></div>
<div id="slideshow4" class="slide" style="display: none"><div>frame 4div></div>

<script type="text/javascript">
    
    start_slideshow(1, 4, 2000);
    
    function start_slideshow(start_frame, end_frame, delay) {
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    function switch_slides(frame, start_frame, end_frame, delay) {
        return (function() {
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            if (frame == end_frame) { frame = start_frame; } else { frame = frame + 1; }
            setTimeout("Effect.Appear('slideshow" + frame + "');", 850);
            setTimeout(switch_slides(frame, start_frame, end_frame, delay), delay + 850);
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script>