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Construction of a computerized device for the electrical conductivity measurements of the liquids at elevated temperatures up to 1500 K is described. The method of four electrodes with double immersion developed by Ohta et al. extensively described in Jpn. Inst. Met. 45, (10) 1036 (1981) was selected. The greatest advantage of this method is that it eliminates the influence of the double layer capacity and all interfacial phenomena occurring during the measurement. The method should be an absolute one, but, as was found in case of corrosive melts (fluorides) at high temperatures, a calibration is necessary. The accuracy of the results obtained by this method lies in the range of ±3% and precision in range of ±1%.

The torsion pendulum is not only a mainstay instrument in the world of precision measurement and gravitational physics, but is important in electrical science, biophysics, petrology, metallurgy, and various other fields of endeavor. Whether used in the ‘‘static’’ (deflection) mode, the ‘‘dynamic’’ (oscillating) mode, or in some more complex configuration, instrumentation of this kind enables one to isolate and measure weak effects that would otherwise be difficult if not impossible to observe against the background gravitational field of the earth. In this review, we present a brief history of fiber‐suspended apparatus and assess the fundamental limits of performance of the dumbbell pendulum. We then inventory the different versions of such systems presently used by gravitational physicists and discuss the various interrogation techniques used to monitor the movement of the suspended test mass. Next, we tabulate some of the applications for torsion instruments outside of gravitational physics, and close with a few comments on the direction of research in this area.

Resistivity measurement is a weighted averaging of local resistivities. We develop a formalism to calculate the weighting function, applying it to square van der Pauw samples and to linear and square four‐point probe arrays. In each case, some regions of the sample are negatively weighted, but these regions can be reduced or eliminated by van der Pauw averaging. We discuss negative weighting, which we feel is responsible for spurious reports of superconductivity above room temperature. We show how a square four‐point array can be more effective at measuring local resistivity than a linear one. Finally, we show how to apply our formalism to anisotropic materials.

We have developed a capacitance displacement sensor based on the elastic deformation of a 150 μm thick diaphragm made up of Cu0.98Be0.02. Displacements up to 50 μm can be detected. The resolution is about 0.1 nm. The time dependence of the dilatation of a relaxor‐ferroelectric (Sr0.61Ba0.39)Nb2O6 single crystal after removing an electric field is investigated using this sensor.

We describe the design of a probe that can be inserted into a SQUID susceptometer (S.H.E. model VTS‐805) for electrical measurements at variable temperature and high magnetic field. This top‐loading probe allows multisample measurements and rapid sample replacement without disturbing the susceptometer.

We present a thorough yet simple approach for synthesizing high Tc superconductors of substantial quality. The approach is accompanied by a step‐by‐step discussion of possible pitfalls as well as a correlation of the sample characteristics to the various preparation procedures. A procedure sufficiently accurate for characterizing the resistance as a function of temperature for a Tc determination is also described.

A novel method of mounting thin samples for electrical measurements is described. A vacuum chuck holds a ceramic mounting plate, which, in turn, holds the sample. Contacts on the mounting plate establish electrical connection to the sample. The attachment of wires directly to the sample is unnecessary.