wheel

var page;

window.onload = function() {
  page = document.getElementsByTagName('html');
  page.addEventListener('DOMMouseScroll', <HANDLER>, false);
}
    
window.mimicWheel = function() {
  var evt = document.createEvent("MouseEvents");
  evt.initMouseEvent('DOMMouseScroll', <OPTIONS> )
  page.dispatchEvent(evt);
}