1842.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



Among the eminent individuals of whom Poitiers was in old time 

 the residence, the memory of none is more respected than that of 

 Ste. Radtgonde, wife of Clotaire I, who, abandoning the pleasures 

 of the world and her high position, established herself in Poitiers, and 

 founded there, about the middle of the sixth century, an abbey, which 

 took the name of St. Croix, from a relic of the true cross given to 

 Radogonde by the emperor Justinian. Near the monastery, but beyond 

 the walls of the city, she built a church for the burial of the sister- 

 hood. This is supposed to have been destroyed by the Normans in 

 108-1, and rebuilt at the expiration of the same century. 



The church, as it now remains, is noticeable for the large span of 

 the vaulting over the nave, which has no aisles. The structure is 

 chie6y of semicircular work, and has a lofty arcade against the side 

 walls of the nave, similar to that already mentioned in the cathedral. 

 The choir has an aisle on either side of it, with a semicircular absis 

 and two small chapels. Beneath the high altar is a chapel, containing 



the remains of Radi'gonde, in a black mcrble tomb of evident antiquity. 

 Externally the church has a square tower at the western end, the 

 upper story of which is octagon. Against the north side of the tower 

 is a circular turret with a conical roof, which renders the general effect 

 of the tower picturesque. The walls of this building, both inside and 

 out, are literally covered with masons' marks, in some cases precisely 

 similar to those about the cathedral. 



The only other church in Poitiers is that of Montiemeuf, which was 

 commenced in lO'li, by Guillaume Guy Geoffroy, Count of Poitiers, 

 but was not completed till twenty years after«-ards : the choir was 

 afterwards rebuilt. An attempt has been made to render the whole 

 of the interior classical, by sculpturing an egg and tongue around the 

 capitals of the columns, and other unwise contrivances. On the roof 

 outside are two turreU, with conical roofs and arched openings, similar 

 to those at Notre Dume la Grande, but smaller and more rude. 



ROBERT B. DOCKRAY'S SELF-ACTING RAILWAY SIGNAL. 

 Fig. 1. Fig. 3. Fig. 4. 



Fig. 5. 



UfM 



Fig. 2. 



The intention of this signal is to notify to an approaching engine- 

 driver, that a preceding train has passed any given point upon a rail- 

 way at a certain interval of time before him. It is proposed to fix it 

 at the entrances to tunnels, in deep cuttings, where the curvature of 

 the road olMtructs the sight, or in any other position where it may be 

 thought desirable to warn the engine-drivers, without the expence of 

 having policemen in constant attendance to give the necessary signals. 



Description of the Dhawtngs. 



Fig. 1, is a section through the signal, ond one line of railway. 



Fig. 2, is a section and elevation taken through the connecting rod, 

 and parallel with the line. 



Fig. 3, is an elevation of the disc and lamp head, showing the face 

 of the clock, figured 5, Kl, and l.'i minutes. 



Figs, -i and S arc sections of the lamp head. 



