Page:Messungen an Becquerelstrahlen.djvu/5

 that I refuted this theory by my experiments.

Therefore, it is still only about the question: whether the theory or 's theory.

In the investigation of this question, I was led by the following viewpoints:

1. It was desirable, to investigate a velocity range (being as large as possible) of rays, because only in this way, the sought velocity function can be determined with certainty. Rays that are too fast had to be excluded, because the percentage errors become too great due to their slight deflectability.

2. Since the specific charge assumes (at very slight velocities) the same value for all relevant theories, also rays being as slow as possible had to be investigated in order to determine $$\tfrac{\epsilon}{m_0}$$.

It was indeed achieved by me, that rays of ⅓ of the speed of light are deflected and radiographically fixated. This is also of especial importance, because the investigation remains confined to a single area. It was avoided to resort to comparisons with cathode-rays values. In my point of view, the previous measurements of cathode rays were namely made (with exception of 's) under hardly controllable circumstances, by using an energy equation for the calculation of the velocity, which hardly accounts for the complicated energy changes in the vicinity of the cathode. The processes taking place at the cathode, are too little investigated, to serve as a foundation of the calculations. That also the Zeeman effect (at the current state of research) can give no information about the specific charge of the electron, can be seen from the deviating values, which have been given from the investigation of the spectra of various metals at strong and weak fields.

3. A main requirement was the precision of the measurement of the apparatus constants. I believe that I have gone so far in this respect, as it was allowed by the current physical technology. The apparatuses were made with great skill and understanding by the renowned firm in Bonn. In the following, I give a short overview concerning the most important auxiliary measurements.

I. The electric field.

The electric field of the condenser was given from the measurement of the potential difference of an accumulator battery of 320 elements, and the thickness of the quartz plates which determined the distance of the condenser plates. After every measurement, the potential difference was measured by the compensation method. The thickness measurement is based on the following arrangement: The arm balance of a fine balance was used as a lever, whose rotation axis was the knife edge; the other end of the lever rested upon an optical plane plate. On the arm balance, a vertically located mirror was mounted, in which a fine platinum wire was mirrored. A fine cathetometer of was adjusted to the image, and if one moved the quartz plate (which was to be measured) between lever and optical plate, then the mirror image was displaced. The cathetometer was again adjusted and read. A simple calculation then gave the thickness of the plate of 0,25075 mm.

II. The magnetic field.

The solenoid field was so measured, that its magnetic effect upon a magnetic needle suspended in the interior at a quartz string, was compensated by a coil (being exactly measurable and winded on marble) which was moved over the solenoid. $$ H = 23\mbox{,} 24\partial$$ was given as the average field strength, while $$ H = 23\mbox{,} 19\partial$$ in the center of the solenoid, where $$\partial$$ was measured in Ampere. The current was provided by the urban center, and was regulated by means of a precision-Ampere-meter and a constant resistance. The constancy was so good in general, that one could be assured, that the solenoid current and thus the magnetic field remained constant up to one-thousandth.

The results.

Every single of the obtained curves allowed to determine the specific charge of the electron as a function of velocity, and thus to decide the question concerning the sought natural law. For the purpose of this report, however, I preferred to calculate (from a series of curves ) the maxima $$Z_m$$ of deflection, which were read by means of a cathetometer. Thus one obtains results, which were achieved under manifold experimental conditions. One avoids the already given and somewhat complicated calculations, whose discussion would lead too far at this place. In the following table, I have put together the results. Regarding the first series, it