Hi javascript gurus,

I have a table with a structured as below. What I want to do is place the id abc into an array like so myarray=[a,b,c];
I know that document.getElementById goes to the table called waterloo and getElementsByTagName('td') gets all the tds
then I am looping over them all. All the alert gives me are three commas like so ,,,

Any help would be great
<table id="waterloo">
         <td id="a"></td>
         <td id="b"></td>
          <td id="c"></td>
   var  myTdId =[];
	var x= document.getElementById(formId).getElementsByTagName('td');

	for (var i=0; i<x.length; i++) {
   	    if (x[i].hasOwnProperty) {
          alert (myTdId);