Settlers poured west (many using the canal) into Michigan , Ohio , Indiana , and Illinois ,

places from which they could ship farm produce via the Erie canal to be marketed in the

east ; in return, barge loads of manufacturedgoods and supplies went west .여기에서 places from which 부분이 해석이 안되요...부탁드립니다.

which가 무엇을 대신한거죠....으아