var chap_array = new Array(
    ["24 - Volume 24",'24'],

    ["23 - Volume 23",'23'],

    ["22 - Volume 22",'22'],

    ["21 - Volume 21",'21'],

    ["20 - Volume 20",'20'],

    ["19 - Volume 19",'19'],

    ["18 - Volume 18",'18'],

    ["17 - Volume 17",'17'],

    ["16 - Volume 16",'16'],

    ["15 - Volume 15",'15'],

    ["14 - Volume 14",'14'],

    ["13 - Volume 13",'13'],

    ["12 - Volume 12",'12'],

    ["11 - Volume 11",'11'],

    ["10 - Volume 10",'10'],

    ["9 - Volume 09",'9'],

    ["8 - Volume 08",'8'],

    ["7 - Volume 07",'7'],

    ["6 - Volume 06",'6'],

    ["5 - Volume 05",'5'],

    ["4 - Volume 04",'4'],

    ["3 - Volume 03",'3'],

    ["2 - Volume 02",'2'],

    ["1 - Volume 01",'1']
);
for (var i=0; i<chap_array.length; i++) {
    document.getElementById('id_chapter_1').options[i] = new Option(chap_array[i][0],chap_array[i][1]);
    if (document.getElementById('id_chapter_2')) {
        document.getElementById('id_chapter_2').options[i] = new Option(chap_array[i][0],chap_array[i][1]);
    }
}