{TAIL ~ The Solvay process} uses poisonous ammonia gas with a complex column system to extract {HEAD ~ the said products} 
{ TAIL ~ The Solvay process } uses poisonous ammonia gas with a complex column system to extract { HEAD ~ the said products }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD