( ( ( ( 1660 ( - ( ( Robert Boyle ) - ) ) ) - ) ( Proved ( that ( ( for ( sound ( to exist ) ) ) ( , ( there ( ( had ( to ( be ( air ( for it ) ) ) ) ) ( to ( vibrate against ) ) ) ) ) ) ) ) ) . )
(ROOT (NP (NP (CD 1660)) (PRN (: -) (NP (NNP Robert) (NNP Boyle)) (: -)) (: -) (NP (NP (NNP Proved)) (SBAR (IN that) (S (PP (IN for) (NP (NN sound) (S (VP (TO to) (VP (VB exist)))))) (, ,) (NP (EX there)) (VP (VBD had) (S (VP (TO to) (VP (VB be) (NP (NP (NN air)) (PP (IN for) (NP (PRP it))))))) (S (VP (TO to) (VP (VB vibrate) (PP (IN against))))))))) (. .)))
1660- Robert Boyle- -Proved that for sound to exist, there had to be air for it to vibrate against.
(ROOT (S (NP (NP (CD One)) (PP (IN of) (NP (DT the) (JJS earliest) (NN air) (NNS pumps)))) (VP (VBD was) (VP (VBN made) (PP (IN by) (NP (JJ robert) (NN boyle))))) (. .)))