var num=0;

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  ['images/Investigations/Invest20090103_03.JPG','Moving Light Anomaly','3/16 - Moving Light Anomaly'],
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  ['images/Investigations/Invest20090103_06.JPG','Multiple Light Anomalies','6/16 - Multiple Light Anomalies'],
  ['images/Investigations/Invest20090103_07.JPG','Light Anomaly','7/16 - Light Anomaly'],
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  ['images/Investigations/Invest20090103_09.JPG','Multiple Light Anomalies','9/16 - Multiple Light Anomalies'],
  ['images/Investigations/Invest20090103_10.JPG','Multiple Light Anomalies','10/16 - Multiple Light Anomalies'],
  ['images/Investigations/Invest20090103_11.JPG','Moving Light Anomaly','11/16 - Moving Light Anomaly'],
  ['images/Investigations/Invest20090103_12.JPG','Multiple Light Anomalies','12/16 - Multiple Light Anomalies'],
  ['images/Investigations/Invest20090103_13.JPG','Light Anomaly','13/16 - Light Anomaly'],
  ['images/Investigations/Invest20090103_14.JPG','Light Anomaly','14/16 - Light Anomaly'],
  ['images/Investigations/Invest20090103_15.JPG','Light Anomaly','15/16 - Light Anomaly'],
  ['images/Investigations/Invest20090103_16.JPG','Light Anomaly','16/16 - Light Anomaly']
]

function slideshow(slide_num) {
  document.getElementById('mypic').src=imgArray[slide_num][0];
  document.getElementById('mypic').alt=imgArray[slide_num][1];
  document.getElementById('burns').innerHTML=imgArray[slide_num][2];
}

function slideshowUp() {
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  num = num % imgArray.length;
  slideshow(num);
}

function slideshowBack() {
  num--;
  if (num < 0) {num=imgArray.length-1;}
  num = num % imgArray.length;
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}
