Batteries 20 may be conveniently mounted in {HEAD ~ a spiral formed rod} 22 mounted on the framework of {TAIL ~ the apparatus} 
Batteries 20 may be conveniently mounted in { HEAD ~ a spiral formed rod } 22 mounted on the framework of { TAIL ~ the apparatus }
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL