(new Image()).src = "menu2_1.jpg";
(new Image()).src = "menu3_1.jpg";
(new Image()).src = "menu4_1.jpg";
(new Image()).src = "menu5_1.jpg";
 
window.onload = function()
{
document.picture2.onmouseover = function(){ document.picture2.src="img/menu2_1.jpg"; }
document.picture2.onmouseout = function() { document.picture2.src="img/menu2.jpg"; }
document.picture3.onmouseover = function(){ document.picture3.src="img/menu3_1.jpg"; }
document.picture3.onmouseout = function() { document.picture3.src="img/menu3.jpg"; }
document.picture4.onmouseover = function(){ document.picture4.src="img/menu4_1.jpg"; }
document.picture4.onmouseout = function() { document.picture4.src="img/menu4.jpg"; }
document.picture5.onmouseover = function(){ document.picture5.src="img/menu5_1.jpg"; }
document.picture5.onmouseout = function() { document.picture5.src="img/menu5.jpg"; }
}