Altogether this church, owing to its fine character, and the retention of almost all its original features and proportions unaltered, deserves to be known and visited by all ecclesiologists, who travel along the north-of-France railway to Paris. A few miles farther on the left rises the fine church of S. Leu, which I have known for a long time, and which deserves, as I think, very much more notice and study than it appears to have received. The plan, situation, details, and style (early first-pointed) are all alike of the best, and I know few, even among French churches, which impress me more strongly with the thorough goodness and nobility of their style. The east end of the church rises from the precipitous edge of a rock, which elevates the whole building finely above the level of the _riant_ valley of the Oise. It was attached, I believe, to a Benedictine abbey, the other buildings of which are all in a most advanced state of decay. The church fortunately, though much out of repair, and in some points altered into flamboyant, is nevertheless sufficiently perfect for all purposes of study. It consists in plan of two western towers (the north-west tower being only in part built) then six bays of nave and aisles, three bays of choir, and an apse (circular on plan) of seven bays; round the apse is the procession path, and four chapels, also circular on plan, lighted by two windows, so that one of the groining shafts is placed opposite the centre of the arch into each, and over the altars. In place of the fifth chapel on the north side, a circular recess is formed in the external wall of the procession path, so as to make space for an altar without forming a distinct chapel. I should be disposed to say that this was the original scheme of the church, afterwards altered and much improved by the substitution of larger and distinct chapels.[16] The central chapel of the apse has the unusual feature of another chapel above it, on a level with the triforium, adding much to the picturesque effect of the east end. In addition to the western steeples there are gabled towers which rise above the aisles on each side of the choir, and the church is remarkable, like the church at Mantes, for the absence of transepts. Perhaps, as the internal length is not quite two hundred feet, this is of some advantage to the general effect. A considerable change has at some time been effected in the external appearance of the east end, for on examination I found that each bay of the triforium was formerly lighted by two lancet windows between the clerestory and the roof over the aisles. My impression is, that this must have been altered when the chapels round the apse were erected and within a very short time of the original construction of the church; but whatever the reason, the church has lost much by the alteration. The six bays of the nave appear to have been built after the west end and the choir. The latter has a