var chap_array = new Array(
    ["15 - Emissary from Beyond the Gate",'15/01'],

    ["14 - Chain",'14/00-cover'],

    ["13 - The Water Dragon Rises",'13/01'],

    ["12 - Wild Beast",'12/01'],

    ["11 - The Beast Within",'11/01'],

    ["10 - The Student Council of 10",'10/01'],

    ["9 - Unstoppable Power",'9/01'],

    ["8 - Wolf's Breath",'8/01'],

    ["7 - Tears That Will Never Dry",'7/01-02'],

    ["6 - The Chosen One",'6/001'],

    ["5 - The Spiral of Battle",'5/01'],

    ["4 - The Second Awakening",'4/01'],

    ["3 - Mysterious School",'3/01'],

    ["2 - One Who Opens the Door",'2/01-02'],

    ["1 - I Only Belong to You",'1/00']
);
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]);
    }
}