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The zero field moment of Gd has been measured at 4.2K for a single crystal prepared by solid state electrotransport. It is magnetically very soft: the moment is (7.630+or-0.010) mu B per atom in the b direction and is slightly smaller in the c direction. The conduction electron polarization is 15% higher than previously estimated. Due to its small value the conduction electron susceptibility could not be measured accurately.

High field (30 MA m-1) magnetization measurement at 4.2K and 20.4K on samarium single crystals are reported together with low field studies from 1.8K to 130K. The susceptibility results are analyzed in terms of independent contributions from the moments on the cubic and hexagonal sites (which order antiferromagnetically at 14K and 109K respectively), plus a temperature independent susceptibility. At 4.2K a spin-flop transition on the cube sites was observed around 21.6 MA m-1. Using one anisotropy and two exchange parameters a molecular field model correctly describes the main features of the behaviour on the cubic sites, and their saturation moment is calculated to be 0.47 mu B/atom.

The magnetization of bismuth single crystals has been measured in very high magnetic fields up to 340 kG. Along the binary and the bisectrix axes the data (at 1.5 K) show small but significant deviations from linearity, but along the trigonal axis the deviation is much smaller and barely significant.

Magnet coils are investigated which can produce magnetic fields of 15–40 MA/m (200–500 kOe) during working times of the order of 0.1 sec. These fields are suited for measurements in highly conducting materials. The coils are precooled to 20°K or 77°K and the Joule heat is not removed during the pulse. In Sec. I the thermal limitations of this method are reviewed. Plots are given for the optimum dimensions and current densities for coils producing a specified field during a specified time, minimizing the necessary power supply. Details of a magnet constructed along these lines are given. The maximum field produced by this coil, 16 MA/m (200 kOe) during 0.3 sec, however, proved to be determined by mechanical instabilities. These problems are reviewed in Sec. II. Calculations of the Lorentz force and the internal stresses resulting from it were carried out taking the elastic and plastic properties of copper and insulation into account. It is shown theoretically that a magnet stable to 35 MA/m (440 kOe) can be built from hard drawn copper if a reinforcing steel cylinder is used at a certain radius inside the coil.

The magnetization of NdAl 2 single crystals was measured at 4.2, 20.3 and 77 K, in magnetic fields up to 35 tesla applied in the 〈100〉, 〈110〉 and 〈111〉 directions. The magnetization in these directions may be described theoretically, without any fitting, in terms of two cubic crystalline electric field parameters and one molecular field constant which have been taken from inelastic neutron scattering data. 5

De Haas-van Alphen oscillations have been observed in the magnetization of a power sample of ln3 Yb and are ascribed to a small spherical part of the Fermi surface.

The non-linearity of the magnetization of Pd at 4.2°K has been determined in semi-continuous fields up to 325 kOe. The value of β in the expression M = χ H (1 + βH 2 ) is found to be positive, β = (9.5 ± 1.7) × × 10 −18 m 2 /A 2 ≙ 6 × 10 −14 Oe −2 .