Disclosed herein is a cooling roll which can provide bonded a magnet having excellent magnetic properties and having excellent reliability. A melt spinning apparatus is provided with a tube 2 having a nozzle 3 at the bottom thereof, a coil 4 for heating the tube and cooling roll 5 having a circumferential surface 53 in which dimple correcting means is provided. A melt spun ribbon 8 is formed by injecting the molten alloy 6 from the nozzle 3 so as to be collided with the circumferential surface 53 of the cooling roll 5 in an inert gas atmosphere (ambient gas) such as helium gas, so that the molten alloy 6 is cooled and then solidified. In this process, dimples to be produced on a roll contact surface of the melt spun ribbon are divided by the dimple correcting means, thereby preventing formation of huge dimples.