function menu_link(num)
{
	switch(num)

	{

	  case 1:window.location="index.html" ;break;

	  case 2:window.location="about_us.html" ;break;

	  case 3:window.location="catalog.html" ;break;

	  case 4:window.location="getting_started.html" ;break;

	  case 5:window.location="tutorial.html" ;break;

	  case 6:window.location="new_page.html" ;break;

	}
}