if (document.layers)
{
        visible = 'show';  hidden = 'hide';
}
else if (document.all)
{
        visible = 'visible';  hidden = 'hidden';
}
function DivLeft(l)
{
        this.l = l;
}

var div1 = new DivLeft('Layer1');
var div2 = new DivLeft('Layer2');
var div3 = new DivLeft('Layer3');
var div4 = new DivLeft('Layer4');
var div5 = new DivLeft('Layer5');
var div6 = new DivLeft('Layer6');
var div7 = new DivLeft('Layer7');
var div10 = new DivLeft('Layer10');
var div11 = new DivLeft('Layer11');

DivLeft.prototype.show = function()
{
        if (document.layers)
        {
                div = document.layers[this.l];
        }
        else if (document.all)
        {
                div = document.all(this.l).style;
        }
        div.visibility = visible;
}
DivLeft.prototype.hide = function()
{
        if (document.layers)
        {
                div = document.layers[this.l];
        }
        else if (document.all)
        {
                div = document.all(this.l).style;
        }
                div.visibility = hidden;
}