Moorhouse had realised that it was necessary that there should be a worthy cathedral at Melbourne. After much discussion the site was chosen as the corner of Swanston and Flinders Streets and William Butterfield as the architect, but the raising of the money became a great problem. He was heartened by a gift of £10,000 from Sir William Clarke, and even more by the receipt of £5000 from an anonymous Presbyterian, who was subsequently found to be Francis Ormond. The foundation stone of St Paul's Cathedral, Melbourne was laid on 13 April 1880 and the building was completed except for the spires in 1891. Another important question of the time was the framing of the constitution of the Church in Australia. A general synod was held at Sydney, and in the absence of the bishop of Sydney in England, Moorhouse was chosen to be chairman. The problems to be dealt with held many difficulties and at the previous synod held five years before, time had been wasted and tempers tried, without result. There can be no question that the eloquence and earnestness of Moorhouse had much to do with the success of the meeting. He was able to report: "We worked like brothers without a single casual or vexatious objection. . . . I believe we have settled our constitution on primitive lines, and in such a way that no deadlock can arise in the future."