Removed in 1844, with many other officers, by the incoming Native American Common Council, he was appointed comptroller on a change of administration in the spring of 1845, by a unanimous vote, and held that office under Democratic and Whig rule more than three years, when he resigned to accept the vicepresidency of the Delaware and Hudson Canal Company. After one year he withdrew to accept a similar position in the Pennsylvania Coal Company, of which he soon after became president. To the interests of this corporation he devoted the best qualities of his head and heart, and in its service he sacrificed his health and possibly his life.

In conducting the successful defense of his company against adverse litigation, begun in 1853, continued during a period of about seventeen years and involving claims amounting to millions of dollars, Mr. Ewen displayed great ability and wonderful capacity for work. At the beginning of the litigation, perceiving that his efficiency in directing the defense would be greatly increased by his admission to the bar, he unhesitatingly undertook the study of law, which he prosecuted in season and out of season, so that in a few months he was regularly admitted to l)ractice in the courts of this State. Availing himself of this ])rivilege, he took testimony covering thou- t sands of pages and made at the close an able argument, filling a large volume in itself, covering all that part of the case involving, especially, questions of civil engineering, with which he had been familiar from boyhood.