Thus, when a viewer views the exterior of the lamp generally in elevation, the cover selectively displays different designs to {HEAD ~ the viewer} depending on the illumination state of {TAIL ~ the device} 
Thus , when a viewer views the exterior of the lamp generally in elevation , the cover selectively displays different designs to { HEAD ~ the viewer } depending on the illumination state of { TAIL ~ the device }
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 TAIL TAIL TAIL TAIL TAIL TAIL