function Load(i) {
	// load the photo
	document.images.main.src=photos[i];
        // set the counter info
	pic1 = document.getElementById("picNo") ;
        pic1.innerHTML = i + 1 ;
	pic2 = document.getElementById("picTotal") ;
        pic2.innerHTML = photos.length ;
        // set the author info
	auth = document.getElementById("author") ;
        auth.innerHTML = author[i];

}

function Next() {
        i = index + 1 ;
        if (i < photos.length) {
        	index = i ;
        } else {
        	index = 0 ;
       	}
        Load(index);

	//document.images.main.src=photos[index];
	//auth = document.getElementById("author") ;
        //auth.innerHTML = author[index];
}

function Back() {
        i = index - 1 ;
        if (i >= 0) {
        	index = i ;
        } else {
        	index = photos.length - 1;
        }
        Load(index);
	//document.images.main.src=photos[index];
}