Simplify the following text for a Grade 16 native English-speaking person.
Original: The Russian chemist and science historian Lev Chugaev has characterized him as `` a chemist of genius , first-class physicist , a fruitful researcher in the fields of hydrodynamics , meteorology , geology , certain branches of chemical technology ( explosives , petroleum , and fuels , for example ) and other disciplines adjacent to chemistry and physics , a thorough expert of chemical industry and industry in general , and an original thinker in the field of economy . ''
Simplified: The Russian chemist and science historian L.A. Tchugayev has characterized him as `` a chemist of genius , first-class physicist , a fruitful researcher in the fields of hydrodynamics , meteorology , geology , certain branches of chemical technology ( explosives , petroleum , and fuels , for example ) and other disciplines adjacent to chemistry and physics , a thorough expert of chemical industry and industry in general , and an original thinker in the field of economy . ''