He went down on his knees, examining it minutely, even going so far as to smell it. 
( He ( ( ( ( ( went down ) ( on ( his knees ) ) ) , ) ( ( ( ( ( examining it ) minutely ) , ) even ) ( ( going ( so ( far as ) ) ) ( to ( smell it ) ) ) ) ) . ) )
(ROOT (S (NP (PRP He)) (VP (VBD went) (PRT (RP down)) (PP (IN on) (NP (PRP$ his) (NNS knees))) (, ,) (S (VP (VP (VBG examining) (NP (PRP it)) (ADVP (RB minutely))) (, ,) (ADVP (RB even)) (VP (VBG going) (ADVP (RB so) (RB far) (RB as)) (S (VP (TO to) (VP (VB smell) (NP (PRP it))))))))) (. .)))
He examined it upon his hands and knees. 
( He ( ( ( examined it ) ( upon ( his ( ( hands and ) knees ) ) ) ) . ) )
(ROOT (S (NP (PRP He)) (VP (VBD examined) (NP (PRP it)) (PP (IN upon) (NP (PRP$ his) (NNS hands) (CC and) (NNS knees)))) (. .)))