function updateClock ( )
{
  var currentTime = new Date ( );

  var currentHours = currentTime.getUTCHours ( );
  var currentMinutes = currentTime.getUTCMinutes ( );
  var currentSeconds = currentTime.getUTCSeconds ( );

  // Pad the minutes and seconds with leading zeros, if required
  currentMinutes = ( currentMinutes < 10 ? "0" : "" ) + currentMinutes;
  currentSeconds = ( currentSeconds < 10 ? "0" : "" ) + currentSeconds;

  // Choose either "AM" or "PM" as appropriate
  //var timeOfDay = ( currentHours < 12 ) ? "AM" : "PM";

  // Convert the hours component to 12-hour format if needed
  currentHoursNY = currentHours - 4;
  currentHoursNY = ( currentHoursNY < 0 ) ? currentHoursNY + 24 : currentHoursNY;
  currentHoursNY = ( currentHoursNY < 10 ? "0" : "" ) + currentHoursNY;

  currentHoursAB = currentHours + 3;
  currentHoursAB = ( currentHoursAB > 24 ) ? currentHoursAB - 24 : currentHoursAB;
  currentHoursAB = ( currentHoursAB < 10 ? "0" : "" ) + currentHoursAB;
              
  // Convert an hours component of "0" to "12"
  //currentHours = ( currentHours == 0 ) ? 12 : currentHours;

  // Compose the string for display
  var currentTimeStringNY = currentHoursNY + " : " + currentMinutes + " : " + currentSeconds;
  var currentTimeStringAB = currentHoursAB + " : " + currentMinutes + " : " + currentSeconds;

  // Update the time display
  document.getElementById("clockNY").firstChild.nodeValue = currentTimeStringNY;
  document.getElementById("clockAB").firstChild.nodeValue = currentTimeStringAB;
}