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  ['images/Investigations/Invest20081124_03.JPG','Multiple Light Anomalies','3/7 - Multiple Light Anomalies'],
  ['images/Investigations/Invest20081124_04.JPG','Moments Later','4/7 - Moments Later'],
  ['images/Investigations/Invest20081124_05.JPG','Multiple Light Anomalies','5/7 - Multiple Light Anomalies'],
  ['images/Investigations/Invest20081124_06.JPG','Light Anomaly','6/7 - Light Anomaly'],
  ['images/Investigations/Invest20081124_07.JPG','Light Anomaly','7/7 - Light Anomaly']
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function slideshow(slide_num) {
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  document.getElementById('mypic').alt=imgArray[slide_num][1];
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function slideshowUp() {
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