// Set the default "show" mode to that specified by W3C DOM
// compliant browsers

var showMode = 'table-cell';

// However, IE5 at least does not render table cells correctly
// using the style 'table-cell', but does when the style 'block'
// is used, so handle this

if (document.all) showMode='block';

// This is the function that actually does the manipulation

function toggleVis(btn){


		// First isolate the checkbox by name using the
		// name of the form and the name of the checkbox
	
		btn = document.forms['tcol'].elements[btn];
	
		// Next find all the table cells by using the DOM function
		// getElementsByName passing in the constructed name of
		// the cells, derived from the checkbox name
	
		cells = document.getElementsByName('t'+btn.name);
	
		// Once the cells and checkbox object has been retrieved
		// the show hide choice is simply whether the checkbox is
		// checked or clear
	
		mode = btn.checked ? showMode : 'none';
	
		// Apply the style to the CSS display property for the cells

	    for(j = 0; j < cells.length; j++) cells[j].style.display = mode;
	
}