图片总是往上多走一个


<table bgcolor="#FFFFFF" width="778"  border="0" align="center" cellpadding="0" cellspacing="0" id="table3">
  <tr>
    <td>
    
    
       <div align="center" id=icefable1>
         <table width="778" border="0" align="center" cellpadding="1" cellspacing="1" bgcolor="#FFFFFF" id="table4">
           <tr>
             
             
            <td align="center"> 
<img border="0" src="images/zhongxiaoxueguanli5.jpg" width="91" height="128" vspace="2"><br>
中小学管理</td>
             
             <td align="center">
<img border="0" src="images/2.jpg" width="90" height="128" vspace="2"><br>
英语沙龙</td>
             
             <td align="center">
<img border="0" src="images/3.jpg" width="90" height="128" vspace="2"><br>
世界知识</td>
             
             
            <td align="center"> 
              <img border="0" src="images/4.jpg" width="90" height="128" vspace="2"><br>
摄影世界</td>
             
             <td align="center">
<img border="0" src="images/5.jpg" width="90" height="128" vspace="2"><br>
特别关注</td>
             
             <td align="center">
<img border="0" src="images/6.jpg" width="90" height="128" vspace="2"><br>
课堂内外</td>
             
             <td align="center">
<img src="images/7.jpg" width="90" height="128" border="0" title="青年文摘" vspace="2"><br>
八小时以外</td>
             
             <td align="center">
<img border="0" src="images/8.jpg" width="90" height="128" vspace="2"><br>
读者</td>
             
           </tr>
         </table>
         <table width="778" border="0" align="center" cellpadding="1" cellspacing="1" bgcolor="#FFFFFF" id="table5">
           <tr>
             
             <td align="center">
<img border="0" src="images/9.jpg" width="90" height="128" vspace="2"><br>
求是</td>
             
             <td align="center">
<img border="0" src="images/10.jpg" width="90" height="128" vspace="2"><br>
中外文摘</td>
             
             <td align="center">
<img border="0" src="images/11.jpg" width="90" height="128" vspace="2"><br>
大众医学</td>
             
             <td align="center">
<img border="0" src="images/12.jpg" width="90" height="128" vspace="2"><br>
少儿美术</td>
             
             <td align="center">
<img border="0" src="images/13.jpg" width="90" height="128" vspace="2"><br>
小说选刊</td>
             
             <td align="center">
<img border="0" src="images/14.jpg" width="90" height="128" vspace="2"><br>
生活周刊</td>
             
             <td align="center">
<img border="0" src="images/15.jpg" width="90" height="128" vspace="2"><br>
政治教与学</td>
             
             <td align="center">
<img border="0" src="images/16.jpg" width="90" height="128" vspace="2"><br>
中国学校体育</td>
             
           </tr>
         </table>
       </div>
       
       <SCRIPT>
       marqueesHeight=152;
       stopscroll=false;
       with(icefable1){
          style.width=0;
          style.height=marqueesHeight;
          style.overflowX="visible";
          style.overflowY="hidden";
          noWrap=true;
          onmouseover=new Function("stopscroll=true");
          onmouseout=new Function("stopscroll=false");
         }
         preTop=0; currentTop=152; stoptime=0;
         icefable1.innerHTML+=icefable1.innerHTML;
         
       
       function init_srolltext(){
         icefable1.scrollTop=0;
         setInterval("scrollUp()",20);
       }init_srolltext();
       
       function scrollUp(){
         if(stopscroll==true) return;
         currentTop+=1;
         if(currentTop==153)
         {
          stoptime+=1;
          currentTop-=1;
          if(stoptime==500) 
          {
          currentTop=0;
          stoptime=0;  
          }
         }
         else {  
          preTop=icefable1.scrollTop;
          icefable1.scrollTop+=1;
          if(preTop==icefable1.scrollTop){
            icefable1.scrollTop=152;
            icefable1.scrollTop+=1;
            
          }
         }
       
       }
       
       </SCRIPT>    
原因: 当滚动二次后图片总是往上多走一个