var counters = {};

function cycleImages(id, maxImages) {
	if (!counters[id]) {
		counters[id] = 1;
	}
	
	var nextImg = '_images/'+id+counters[id]+'.png';
	$(id).src = nextImg;
	counters[id]++;
	
	if (counters[id] >= maxImages) {
		counters[id] = 0;
	}
}