As the temple is forced further laterally outwardly, the finger portion will continue moving toward the front end of the temple until the finger tip firmly abuts the front end of {HEAD ~ the temple}, thereby acting as a positive stop and closing the space between the finger tip and the front end of {TAIL ~ the temple} 
As the temple is forced further laterally outwardly , the finger portion will continue moving toward the front end of the temple until the finger tip firmly abuts the front end of { HEAD ~ the temple } , thereby acting as a positive stop and closing the space between the finger tip and the front end of { TAIL ~ the temple }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL