You can add your images in first-loaded-first displayed order like this:
Demo: http://jsfiddle.net/m1erickson/7w6cb/
var imageURLs=[];
var imgs=[];
imageURLs.push("house100x100.png");
imageURLs.push("house32x32.png");
imageURLs.push("house16x16.png");
for(var i=0;i