A bitter magnet system 13 T.-125 MM. bore usable for investigations at 1.8 K.

One describes a cryomagnetic system mainly aimed at the charaterization of superconducting materials submitted to an external field for two temperatures : 1.8 K and 4.2 K. The originality of the system is to obtain 1.8 K at atmospheric pressure. The system is made of two distinct parts : -A Bitter coil, with a nominal power of 10 MW allowing to obtain more than 13T in a clear bore of 160 mm at room temperature. -A cryostat in which it is possible to insert cylindrical elements with a diameter of 125 mm, equiped with appliances allowing either a traditional use or an use with superfluid helium at atmospheric pressure. This material was built to allow stability experiments in superconducting samples as well as significant length tests of commercial superconducting materials.