Uses of the Round Towers of Ireland, 



185 



construction, but the arches are usually formed with great skill, and of blocks of 

 stone nearly all of equal size. These arches are invariably semicircular, and 

 generally spring from jambs which have an inclination corresponding with 

 those of the doorways and windows, and which usually are without imposts. As 

 a characteristic example of such chancel arches, it will be sufficient to give a 

 view of the interior of Trinity Church at Glendalough : 



This arch is nine feet wide, and ten feet six inches from the present level of 

 the floor, which seems considerably raised, to the key-stone of the arch, and the 

 jambs are six feet high to the spring of the arch. 



I have next to speak of the materials, mode, and style of construction, of 

 the roofs of the primitive Irish churches. 



In the smaller churches of oblong form, without chancels, the roofs appear 

 to have been generally constructed of stone, their sides forming at the ridge a 

 very acute angle ; and this mode of construction was continued, in the con- 

 struction of churches, down to the period of the introduction of the pointed or 

 Gothic style into Ireland, as in the beautiful church called Cormac's Chapel, at 

 Cashel, which was finished in the year 1134, and St. Doulagh's Church, near 

 Dublin, which is obviously of even later date. In the larger churches, how- 



VOL. xx. 2 B 



