{TAIL ~ This reduction state} is sustained until {HEAD ~ the desired effects} are obtained and the temperature may be held to lengthen this reduction 
{ TAIL ~ This reduction state } is sustained until { HEAD ~ the desired effects } are obtained and the temperature may be held to lengthen this reduction
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH