Sliding From left to right always with out back slide from right to left ?

Sliding From left to right always with out back slide from right to left ?

Hi there and really thanks all you for this forums
Im new in jquery and I design a slide show that slides from left to right but when it comes to end or 5th pic it begins to slide back from right to left 
but i want it slides from left to right always and always 
this is query code 
please help me how to fix it that always slides from left to right and has never back slides from right to left ?
the query code and query link is :
<script type="text/javascript" src="jquery-1.2.6.min.js"></script> <script type="text/javascript"> /***      Simple jQuery Slideshow Script     Released by Jon Raasch (jonraasch.com) under FreeBSD license: free to use or modify, not responsible for anything, etc.  Please link out to me if you like it :) ***/ function slideSwitch() {     var $active = $('#slideshow DIV.active');     if ( $active.length == 0 ) $active = $('#slideshow DIV:last');     // use this to pull the divs in the order they appear in the markup     var $next =  $active.next().length ? $active.next()         : $('#slideshow DIV:first');     // uncomment below to pull the divs randomly     // var $sibs  = $active.siblings();     // var rndNum = Math.floor(Math.random() * $sibs.length );     // var $next  = $( $sibs[ rndNum ] );     $active.addClass('last-active');     $next.css({opacity: 0.0})         .addClass('active')         .animate({opacity: 1.0}, 1000, function() {             $active.removeClass('active last-active');         }); } $(function() {     setInterval( "slideSwitch()", 5000 ); }); please help me 
With the Best regard :
Raha