minus = new Image();
minus.src = 'graphics/misc/plus.gif';
function toggleImage(number) {
if (document.getElementById(number).src.match('graphics/misc/plus.gif')) {
document.getElementById(number).setAttribute('src', 'graphics/misc/minus.gif');
}
else {
document.getElementById(number).setAttribute('src', 'graphics/misc/plus.gif');
}
}