Making tiles of a picture

tiles.css

        .tile-ssimg { width: 50px; height: 50px; }
        .tile_1 {background-position: 0px 0px;}
        .tile_2 {background-position: -50px 0px;}
        .tile_3 {background-position: -100px 0px;}
        .tile_4 {background-position: -150px 0px;}
        .tile_5 {background-position: 0px -50px;}
        .tile_6 {background-position: -50px -50px;}
        .tile_7 {background-position: -100px -50px;}
        .tile_8 {background-position: -150px -50px;}
        .tile_9 {background-position: 0px -100px;}
        .tile_10 {background-position: -50px -100px;}
        .tile_11 {background-position: -100px -100px;}
        .tile_12 {background-position: -150px -100px;}
        .tile_13 {background-position: 0px -150px;}
        .tile_14 {background-position: -50px -150px;}
        .tile_15 {background-position: -100px -150px;}
        .tile_16 {background-position: -150px -150px;}