Although erected to the honour of Constantine, this arch commemorates the victories of Trajan, some of the basso-relievos, &c. having been pilfered from one of the arches of Trajan. This accounts for the Dacian captives, whose heads Lorenzo de Medicis broke off and conveyed to Florence, but the theft might not have been so notorious to posterity, had not the artists of Constantine's time added some figures of inferior merit. Forsyth says, "Constantine's reign was notorious for architectural robbery;" and the styles of the two emperors, in the present arch, mar the harmony by their unsightly contrasts. Although the decree for erecting this arch was, without doubt, passed immediately after the defeat of Maxentius, it appears from the monument itself, that the building was not finished and dedicated till the tenth year of Constantine's reign, or the year of Christ 315 or 316. The newly-erected arch opposite the entrance to Hyde Park is from the Roman arch, though, we believe, not from any particular model. In the View of the New Palace, St. James's Park, (in our No. 278,) the arch, to be called the Waterloo Monument, and erected in the middle of the area of the palace, will be nearly a copy of that of Constantine at Rome. In the court-yard of the Tuilleries at Paris, there is a similar arch, copied from that of Septimius Severus. This was formerly surmounted by the celebrated group of the horses of St. Mark, pilfered from Venice, but restored at the peace of 1815. * * * * * THE BEGGAR'S DAUGHTER OF BETHNAL GREEN. _(For the Mirror.)_ The popular ballad of "The Beggar's Daughter of Bednall-Greene" was written in the reign of Queen Elizabeth. It is founded, though without the least appearance of truth, or even probability, on a legend of the time of Henry III. Henry de Montfort, son of the ambitious Earl of Leicester, who was slain with his father at the memorable battle of Evesham, is the hero of the tale. He is supposed (according to the legend) to have been discovered among the bodies of the slain by a young lady, in an almost lifeless state, and deprived of sight by a wound, which he had received during the engagement. Under the fostering hand of this "faire damosel" he soon recovered, and afterwards marrying her, she became the mother of "the comelye and prettye Bessee." Fearing lest his rank and person should be discovered by his enemies, he disguised himself in the habit of a beggar, and took up his abode at Bethnal-Green. The beauty of his daughter attracted many suitors, and she was at length married to a noble knight, who, regardless of her supposed meanness and poverty, had the courage to make her his wife, her other lovers having deserted her on account of her low origin. Before entering, however, upon the ballad, it may not, perhaps, be thought irrelevant to give a brief sketch of the family of the De Montforts.