if (document.images){
	text_off=new Image
	introduction_on=new Image
	themes_on=new Image
	tour_on=new Image
	checklist_on=new Image
	colophon_on=new Image
	links_on=new Image
	press_on=new Image
		
	text_off.src="images/index/text_off.gif"
	introduction_on.src="images/index/introduction_on.gif"
	themes_on.src="images/index/themes_on.gif"
	tour_on.src="images/index/tour_on.gif"
	checklist_on.src="images/index/checklist_on.gif"
	colophon_on.src="images/index/colophon_on.gif"
	links_on.src="images/index/links_on.gif"
	press_on.src="images/index/press_on.gif"
	
}

function chgImg(imgField,newImg){
	if (document.images){
		document[imgField].src=eval(newImg+".src")
	}
	
}