Intelligence and Miscellaneous Articles. 319 



the magnetic separation is about twice as great for 5167-5 as for 

 5183-8. Again, the cadmium lines 3403-7, 3407-7, and 3813-0 

 exhibited the same pressure-shift, but on my plates 3403-7 appears 

 to be unaffected by the field, while the other two lines, although 

 not sharp enough to be measured, are considerably broadened, if 

 not separated. Other examples may be given to the same effect. 



In the paper already cited, Dr. Preston states that he was unable 

 to observe the cases of so-called " reversed polarization " observed 

 by Becquerel and Deslandres in France, and afterwards in this 

 laboratory. Now, while it may very well be that what we observed 

 as a single central line would prove to be a pair in a stronger 

 field, showing the supposed triplet to be a quadruplet of a possible 

 type discussed in Dr. Preston's paper, I am inclined to put more 

 faith in our own results than in his, because he states that he 

 had to make an exposure of four hours to get these lines, and of 

 course could not maintain a strong field for that length of time. 

 ISTot only does a long exposure necessitate a weaker current to 

 excite the electromagnet, but it entails great liability of bad 

 definition in the photograph on account of slight jars about the 

 spectrometer. 



It is probable that no entirely satisfactory results from the 

 Zeeman effect can be secured until a very uniform field of great 

 strength is obtained. Many of the deviations from the common 

 triplet may be due to sensible differences in the strength of the 

 field at different parts of the source of light. — Johns Hopkins 

 University Circular for June 1899, p. 59. 



A POSSIBLE MECHANISM OF MAGNETISATION. 

 BY J. J. TAUDIN CHABOT. 



I. Let two cylindrical steel magnets with their axes parallel be 

 arranged so that their unlike poles are opposite each other; a 

 number of such magnetic pairs, placed in mutually similar positions, 

 may form an extended system. Each several magnet is to be 

 susceptible of rotation about its axis at a fixed distance from the 

 next, and is likewise to be connected with its neighbours, at the 

 ends and middle alternately, by means of mechanism formed of 

 electrically conducting material (driving-bands as in the annexed 

 sketch, or toothed gearing with intermediate idle wheels), so that 

 on applying proper motive power all the magnets rotate with the 

 same velocity in the same sense. 



Such a combined system, formed of an even number of parallel 

 magnets with their similar poles presented alternately in 

 opposite directions, would exert no magnetic force at a distant 

 point and would possess no directive force in a uniform magnetic 

 field. But what would be the result of a common rotation of its 

 constituent elementary magnets in the manner indicated ? 



Each magnet will now be traversed by an electric current 

 flowing either from the middle to the two ends or from the ends 

 towards the middle ; and inasmuch as the magnets are mutually 

 connected at the ends and at the middle by electric conductors 



