The Derwent at Derby is spanned by several handsome bridges. The oldest and most picturesque of these structures is St. Mary's. At the foot of the bridge is an ancient chapel where "the busy burgesses or men-at-arms turned aside for a brief silent prayer before crossing the Derwent and plunging into the forests that stretched out before them on the other side of the river." This mediæval bridge-chapel of Our Lady is now used as a mission-room in connection with the church of St. Alkmund. Just below the bridge, on an island, stands the first silk-mill ever erected in England. It is a vast pile of time-toned brick, pierced with as many windows as there are days in the year, and surmounted by a curious bell-tower. The history of the silk trade in Derby dates back to the opening days of the last century. At that period the Italians held secret the art of silk-throwing, and monopolised the market. John Lombe, an ambitious young fellow, full of spirit, an excellent draughtsman, and a capable mechanic, determined to acquire the secret. He visited Italy, and brought to Derby from Piedmont models of the coveted machinery, together with two native craftsmen who had favoured his enterprise and secured his safety. The Derby Corporation leased to Lombe the island swamp in the Derwent, where he erected in 1718 the present immense mill on a foundation of oaken piles. It cost him £30,000, but his manufactures were a superlative success, and the Italian monopoly was driven out of the market. But Lombe did not live more than two years to reap the rich result of his labours. Treachery was at work, and he was poisoned at the hands of an Italian woman who was employed by the Piedmontese, and who contrived to escape the punishment due to her crime. Lombe, who was only twenty-nine when he thus tragically perished, was buried at All Saints', a church whose tower is one of the glories of the midland counties. Here, too, rest several members of the Cavendish family, their virtues commemorated in monumental marble; and there is a magnificent monument to the famous Countess of Shrewsbury, the friend of Queen Elizabeth, but better known as "Building Bess of Hardwick."