Sentence:  He was , however , fortunate in his contact with Prof. J. G. L. Manthey ( 1769 - 1842 ) , teacher of <WSD>chemistry</WSD> , who , in addition to his academic chair , was also proprietor of the `` Lion Pharmacy '' in Copenhagen where Oersted assisted him . 
Meaning of the word marked with <WSD> tags:  the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions