The adjustable arm 2 further comprising means for controllably applying {HEAD ~ an axial force} to {TAIL ~ the contacting regions} of the first and second parts of either or both of said base and central housings to supply friction to assist in the maintaining of the positioning of the lamp 
to
The adjustable arm 2 further comprising means for controllably applying { HEAD ~ an axial force } to { TAIL ~ the contacting regions } of the first and second parts of either or both of said base and central housings to supply friction to assist in the maintaining of the positioning of the lamp
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL 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