DELAWARE, a river of the United States, which rises in Catskill Mountains, in New York. In its course it separates Pennsylvania from New York and New Jersey, and loses itself in Delaware Bay, about five miles below Newcastle. It is navigable for a seventy-four gun ship as far as Philadelphia, fifty-five miles above the head of the bay, and about a hundred and twenty from the ocean; for sloops to the head of the tide at Trenton, thirty-five miles above Philadelphia; and for boats a hundred miles farther, but the boat navigation above Easton is very difficult. Its two most important tributaries are the Schuylkill and the Lehigh. The whole length, from its source to the bay, is about three hundred miles. The principal towns on the Delaware, besides Philadelphia, are Easton, Bristol, Trenton, Bordentown, and Burlington.