A high nave and a stained glass window by John Hardman & Co. Dominate the west end. The tower, low in comparison to the nave, marks the old west end before a new narthex was added. The crenellated western tower is decorated by a clerestory, a tableau of the crucifixion and a statue of the Sacred Heart. The interior consists of an aisled nave with rounded sandstone piers and pointed Gothic arches which leads up to a distant sanctuary bathed in a mystical gloom. The wooden buttresses spring from corbells high on the walls in support of the open roof. The quasi-moorish arch and strainer beam is a result of the renovation as seen in a comparison with the original archway. The sanctuary is quite plain with the exception of the Sicilian marble altar introduced in 1897, from Dublin . The sanctuary is lit by two slim lancets placed in memory of Bishop Matthew Quinn, which show the Sacred Heart on the left and St Matthew on the right. Above is a trefoil which portrays the Holy Spirit. The marble altar is the focal point of the cathedral. After Vatican II the mensa was moved forward in order to accommodate the "novus ordo" with the Bishop's throne and celebrant's chairs set behind it. The style of the altar is that of the pre-Vatican II era when the altar served both as the main focal point of the church and as the throne.