var aryImages = new Array();

aryImages[1] = "gallery2/html18.png";
aryImages[2] = "gallery2/html17.png";
aryImages[3] = "gallery2/html19.png";


for (i=0; i < aryImages.length; i++) {
	var preload = new Image();
	preload.src = aryImages[i];
}

function swap(imgIndex, imgTarget) {
	document[imgTarget].src = aryImages[imgIndex];
}