Page:Über die Konstitution des Elektrons.djvu/3

 my greatest gratitude here, I have carried out the experiments in the course of last year, and I shortly report in the following about the general experimental arrangement and the results; a more extended report with a more precise specification of the experimental arrangement, and with the results of all auxiliary measurements etc. shall appear in the Annalen der Physik.

The experimental arrangement was in principle the same as earlier; the main differences consisted in the following:

Instead of the electro magnet used earlier, two superimposed and very strong horseshoe magnets were employed, generating a field which was homogeneous within $$\pm 2$$ along the ray-path, and in consequence of the high age of the magnet it was completely constant (H ca. 140 C. G. S. E.).

The small apparatus containing the grain of radium, the condenser plates serving for the generation of the electric field, and the photographic plate, had ca. the same dimensions as earlier (the whole ray-path = 4cm). All parts, however, were produced with the greatest precision, and the photographic plate was (especially for my experiments) poured upon mirror glass, so that the length of the ray-paths in terms of their single parts, and the "field integrals" relevant for the deflection, could be safely determined to $1/100$mm or to a fraction of one percent. The distance of both condenser plates (that were smoothly cut) was determined by pressing them through two isolated screws against four quartz-plates slided in-between, which were cut from a single plan-parallel plate, and whose thickness was determined as 1.242 mm ± 1&mu; by the company Zeiß.

The course of the electric field along the ray-path was determined, by producing (with 29times magnification) a copy of the whole condenser apparatus, in which the field distribution was determined by means of a oscillating metal mirror of 5mm diameter by observing the oscillation period.

The potential difference on the actual apparatus was produced by means of a high-voltage battery; the maximal voltage amounted ca. 1600 volt. By an automatic seesaw, two Leyden jars connected with the condenser plates where brought to a constant voltage of +V or -V, so that the potential difference of the plates amounted 2V, where V is the available battery voltage. The latter was measured before and after every exposition (which lasted ca. two days) by means of a compensating apparatus and a Weston cell.