function divSwitch(showDiv) {
	// exit point for older browsers
	if (!document.getElementsByTagName) {return null;}
	// hide all dbnav divs
	hideWhat = document.getElementById("dbnav_closed_wrapper");
	hideWhat.style.display = "none";
	hideWhat = document.getElementById("dbnav_artists_wrapper");
	hideWhat.style.display = "none";
	hideWhat = document.getElementById("dbnav_subjects_wrapper");
	hideWhat.style.display = "none";
	hideWhat = document.getElementById("dbnav_styles_wrapper");
	hideWhat.style.display = "none";
	// display the chosen div
	showWhat = document.getElementById(showDiv);
	showWhat.style.display = "block";
	// end function
	return;
}