no longer adequate to meet the needs of a numerically and geographically expanding church. All clergy were supposed to attend annual meetings of the synod, but some years attendance was less than thirty percent. In 1785, a proposal for the creation of a General Assembly went before the synod, and a special committee was formed to draw up a plan of government. Under the plan, the old synod was divided into four new synods all under the authority of the General Assembly. The synods were New York and New Jersey, Philadelphia, Virginia, and the Carolinas. Compared to the Church of Scotland, the plan gave presbyteries more power and autonomy. Synods and the General Assembly were to be "agencies for unifying the life of the Church, considering appeals, and promoting the general welfare of the Church as a whole." The plan included provisions from the Church of Scotland's Barrier Act of 1697, which required the General Assembly to receive the approval of a majority of presbyteries before making major changes to the church's constitution and doctrine. The constitution included the Westminster Confession of Faith, together with the Larger and Shorter Catechisms, as the church's subordinate standard (i.e. subordinate to the Bible) in addition to the (substantially altered) Westminster Directory. The Westminster Confession was modified to bring its teaching on civil government in line with American practices. In 1787, the plan was sent to the presbyteries for ratification. The synod held its last meeting in May 1788. The first General Assembly of the Presbyterian Church in the United States of America met in Philadelphia in May 1789. At that time, the church had four synods, 16 presbyteries, 177 ministers, 419 congregations and an estimated membership of 18,000. 19th century Interdenominational societies The late 18th and early 19th centuries saw Americans leaving the Eastern Seaboard to settle further inland. One of the results was that the PCUSA signed a Plan of Union with the Congregationalists of New England in 1801, which formalized cooperation between the two bodies and attempted to provide adequate visitation and preaching for frontier congregations, along with eliminating rivalry between the two denominations. The large growth rate of the Presbyterian Church in the Northeast was in part due to the adoption of Congregationalist settlers along the western frontier. Not unlike the circuit riders in the Episcopal and Methodist traditions, the presbyteries often sent out licentiates to minister in multiple congregations