imgOn1 = new Image(55, 19); imgOn1.src = "img/kojin_on.gif";
imgOf1 = new Image(55, 19); imgOf1.src = "img/kojin_of.gif";
imgOn2 = new Image(55, 19); imgOn2.src = "img/houjin_on.gif";
imgOf2 = new Image(55, 19); imgOf2.src = "img/houjin_of.gif";
imgOn3 = new Image(125, 19); imgOn3.src = "img/kanshi_on.gif";
imgOf3 = new Image(125, 19); imgOf3.src = "img/kanshi_of.gif";
imgOn4 = new Image(98, 19); imgOn4.src = "img/anzen_on.gif";
imgOf4 = new Image(98, 19); imgOf4.src = "img/anzen_of.gif";
imgOn5 = new Image(85, 19); imgOn5.src = "img/co_on.gif";
imgOf5 = new Image(85, 19); imgOf5.src = "img/co_of.gif";
imgOn6 = new Image(112, 19); imgOn6.src = "img/toi_on.gif";
imgOf6 = new Image(112, 19); imgOf6.src = "img/toi_of.gif";

function m_over(imgNo) {
    document ["img"+imgNo].src = eval("imgOn"+imgNo+".src");
  return true;
}
function m_out(imgNo) {
    document ["img"+imgNo].src = eval("imgOf"+imgNo+".src");
  return true;
}