Rev. JOHN DUDLEY, Mount Morris, Michigan, resided as a teacher at the missionary station, among the Choctaws, in Mississippi, during the years 1830 and 31. In a letter just received Mr. Dudley says:-- "During the time I was on missionary ground, which was in 1830 and 31, I was frequently at the residence of the agent, who was a slaveholder.--I never knew of his treating his own slaves with cruelty; but the poor fellows who were escaping, and lodged with him when detected, found no clemency. I once saw there a fetter for '_the d----d runaways_,' the weight of which can be judged by its size. It was at least three inches wide, half an inch thick, and something over a foot long. At this time I saw a poor fellow compelled to work in the field, at 'logging,' with such a galling fetter on his ankles. To prevent it from wearing his ankles, a string was tied to the centre, by which the victim suspended it when he walked, with one hand, and with the other carried his burden. Whenever he lifted, the fetter rested on his bare ankles. If he lost his balance and made a misstep, which must very often occur in lifting and rolling logs, the torture of his fetter was severe. Thus he was doomed to work while wearing the torturing iron, day after day, and at night he was confined in the runaways' jail. Some time after this, I saw the same dejected, heart-broken creature obliged to wait on the other hands, who were husking corn. The privilege of sitting with the others was too much for him to enjoy; he was made to hobble from house to barn and barn to house, to carry food and drink for the rest. He passed round the end of the house where I was sitting with the agent: he seemed to take no notice of me, but fixed his eyes on his tormentor till he passed quite by us." Mr. ALFRED WILKINSON, member of the Baptist Church in Skeneateles, N.Y. and an assessor of that town, testifies as follows :-- "I stayed in New Orleans three weeks: during that time there used to pass by where I stayed a number of slaves, each with an iron band around his ankle, a chain attached to it, and an eighteen pound ball at the end. They were employed in wheeling dirt with a wheelbarrow; they would put the ball into the barrow when they moved.--I recollect one day, that I counted nineteen of them, sometimes there were not as many; they were driven by a slave, with a long lash, as if they were beasts. These, I learned, were runaway slaves from the plantations above New Orleans. "There was also a negro woman, that used daily to come to the market with milk; she had an iron band around her neck, with three rods projecting from it, about sixteen inches long, crooked at the ends." For the fact which follows we are indebted to Mr. SAMUEL HALL, a teacher in Marietta College, Ohio. We quote his letter. "Mr. Curtis, a journeyman cabinet-maker, of Marietta, relates the following, of which he was an eye witness. Mr. Curtis is every way worthy of credit.