1 7 7 8 ) ▁and ▁hydro gen ▁( 1 7 8 3 ), ▁and ▁opposed ▁the ▁ph log ist on ▁theory . ▁Lav ois ier ▁helped ▁construct ▁the ▁metric ▁system , ▁wrote ▁the ▁first ▁extensive ▁list ▁of ▁elements , ▁and ▁helped ▁to ▁reform ▁chemical ▁nom en cl ature . ▁He ▁predicted ▁the ▁existence ▁of ▁sil icon ▁( 1 7 8 7 ) ▁and ▁was ▁also ▁the ▁first ▁to ▁establish ▁that ▁sul fur ▁was ▁an ▁element ▁( 1 7 7 7 ) ▁rather ▁than ▁a ▁comp ound . ▁He ▁discovered ▁that , ▁although ▁matter ▁may ▁change ▁its ▁form ▁or ▁shape , ▁its ▁mass ▁always ▁remains ▁the ▁same . ▁ ▁Lav ois ier ▁was ▁a ▁powerful ▁member ▁of ▁a ▁number ▁of ▁arist ocr atic ▁coun c ils , ▁and ▁an ▁administrator ▁of ▁the ▁F erme ▁générale . ▁The ▁F erme ▁générale ▁was ▁one ▁of ▁the ▁most ▁h ated ▁components ▁of ▁the ▁An ci en ▁Rég ime ▁because ▁of ▁the ▁prof its ▁it ▁took ▁at ▁the ▁exp ense ▁of ▁the ▁state , ▁the ▁secre cy ▁of ▁the ▁terms ▁of ▁its ▁contract s , ▁and ▁the ▁violence ▁of ▁its ▁armed ▁agents . ▁All ▁of ▁these ▁political ▁and ▁economic ▁activities ▁enabled ▁him ▁to ▁fund ▁his ▁scientific ▁research . ▁At ▁the ▁height ▁of ▁the ▁French ▁Revolution , ▁he ▁was ▁charged ▁with ▁tax ▁fra ud ▁and ▁s elling ▁ad ul ter ated ▁to b acco , ▁and ▁was ▁gu ill ot ined . ▁ ▁Biography ▁ ▁Early ▁life ▁and ▁education ▁Antoine - La urent ▁Lav ois ier ▁was ▁born