In this period, a number of key technological changes  sewing machines that made many more stitches a minute, long knives instead of shears for cutting, and pressing machines.
( ( In ( this period ) ) ( , ( ( ( a number ) ( of ( ( key ( technological changes ) ) ( sewing ( machines ( that ( ( ( ( made ( many ( more stitches ) ) ) ( a minute ) ) , ) long ) ) ) ) ) ) ) ( ( knives ( instead ( of ( shears ( for ( ( ( cutting , ) and ) ( pressing machines ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (DT this) (NN period))) (, ,) (NP (NP (DT a) (NN number)) (PP (IN of) (NP (NP (JJ key) (JJ technological) (NNS changes)) (VP (VBG sewing) (NP (NP (NNS machines)) (SBAR (WHNP (WDT that)) (S (VP (VBD made) (NP (JJ many) (JJR more) (NNS stitches)) (NP (DT a) (NN minute)) (, ,) (ADVP (RB long)))))))))) (VP (VBZ knives) (PP (RB instead) (IN of) (NP (NP (NNS shears)) (PP (IN for) (S (VP (VP (VBG cutting)) (, ,) (CC and) (VP (VBG pressing) (NP (NNS machines))))))))) (. .)))
In this period, various key innovative changes, sewing machines that made numerous more lines a moment, long blades rather than shears for cutting, and squeezing machines.
( ( In ( this period ) ) ( , ( ( ( ( ( various ( key ( innovative changes ) ) ) , ) ( ( sewing machines ) ( that ( ( made ( numerous ( more lines ) ) ) ( a moment ) ) ) ) ) , ) ( long ( ( blades ( rather ( than ( shears ( for ( ( ( cutting , ) and ) ( squeezing machines ) ) ) ) ) ) ) . ) ) ) ) )
(ROOT (S (PP (IN In) (NP (DT this) (NN period))) (, ,) (NP (NP (JJ various) (JJ key) (JJ innovative) (NNS changes)) (, ,) (NP (NP (VBG sewing) (NNS machines)) (SBAR (WHNP (WDT that)) (S (VP (VBD made) (NP (JJ numerous) (JJR more) (NNS lines)) (NP (DT a) (NN moment)))))) (, ,)) (ADVP (RB long)) (VP (VBZ blades) (PP (RB rather) (IN than) (NP (NP (NNS shears)) (PP (IN for) (S (VP (VP (VBG cutting)) (, ,) (CC and) (VP (VBG squeezing) (NP (NNS machines))))))))) (. .)))