 <unk> also resumed business activities upon his return . He invested in a wide variety of businesses and infrastructure , spurring economic activity in the state . His investments ranged widely , including maritime insurance ( where is father @-@ in @-@ law had made his fortune ) , bridges , locks , canals , and textiles . He was a major <unk> in the Middlesex Canal , the <unk> Bridge ( the first to connect Boston to Cambridge ) , and the Boston Manufacturing Company , whose factory proving the single @-@ site production of textiles was in <unk> near his estate . Not all of his ventures panned out : the canal was in the long run a financial failure , as were efforts with other collaborators to develop <unk> Point , the Cambridge side of the <unk> Bridge . The textile mill , however , was a success , and <unk> invested in the <unk> Manufacturing Company . When it decided to locate in what is now Lowell , Massachusetts , <unk> purchased shares in the <unk> of <unk> and <unk> , which operated ( and still owns today ) the Lowell canals . 
