Some experiments upon the relations between ether, matter, and electricity

In the following paper are described a number of experiments, undertaken at the suggestion of Professor H. A. Rowland, upon the relations between ether, matter, and electricity. The theories advanced in the paper as suggestive of the experiments are, to the best of the writer's ability, statements of Professor Rowland's ideas. Unfortunately the sudden illness and death of Professor Rowland prevented him from reviewing the paper. Since the development of the wave theory of light by Huygens in 1678, the most important problem which has confronted the physicist has been the determination of the nature and the properties of the medium which we must imagine to fill all space for the propagation of the waves which give rise to the sensation of light. Numerous ethers have been postulated, each with properties which might account for the phenomenon under consideration, but none of which have made any claim to universal application. Green has developed extensively the elastic solid theory, and has even made estimates of the density and rigidity of the ether. The recent development of the electro‐magnetic theory of light and the location of the electro‐magnetic energy in the ether have demanded properties entirely different from any which could be furnished by a rigid elastic solid, and new ethers have been postulated accordingly. Faraday's discovery of the rotation of the plane of polarization of light in a magnetic field suggested that the particles of matter, or the ether in connection with them, must be in rotation. As a result of the theories proposed by Ampere and Weber, and developed by Maxwell, modern theories of magnetism are based on some kind of rotary or vortical motion in the ether, and if a piece of iron is magnetized, we imagine that the molecules, or something about them, rotate also. Maxwell has tried to detect the presence of any such rotation in an electro‐magnet. With a kind of gyroscope he showed that, if it exists, the angular momentum must be small compared with any quantities which we can measure. An attempt was made, at the suggestion of Professor Rowland, by Mr. Paul McJunkin and the author, to determine within what limit it is possible to say that there is no frictional or viscous resistance in the ether connected with such rotation.