Alkali metal such as {TAIL ~ sodium} within tube 14 is heated to a temperature of from about 300 to 1000 degrees C. by suitable means known in {HEAD ~ the art} 
Alkali metal such as { TAIL ~ sodium } within tube 14 is heated to a temperature of from about 300 to 1000 degrees C. by suitable means known in { HEAD ~ the art }
OTH OTH OTH OTH 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 HEAD HEAD HEAD HEAD HEAD HEAD