Record. xix 



two rings on which it is mounted. From these formulae 

 the latitude (\) of the place of observation is derived, 



- -*- 1 



namely : cos \ = ^m. 



Professor F. E. Nipher made afurthur statement concern- 

 ing his results in the attempt to produce ether waves by the 

 explosion of dynamite. He had obtained some results which 

 seemed to show that magnetic effects could thus be produced. 

 " There is apparently no doubt that great solar outbursts like 

 the one which Professor C. A. Young saw at Sherman in 

 1872,* produce enormous distortions of the ether. Why 

 should it not be possible to reproduce this result? It goes 

 without saying that large sun-spots may be slowly formed, 

 without such ether disturbance, and certainly we can hardly 

 expect to reproduce solar velocities. But terrestrial explo- 

 sions do yield tremors and sound vibrations, and these lead to 

 great experimental difficulties. The nickel-silver coherer can 

 be operated by the sound waves from a tuning fork. The 

 coherer can be either opened or closed by sound waves, when 

 the coherer is properly placed in a magnetic field. The same 

 result may be produced by changes in the magnetic field, due 

 to the slow approach of a horse-shoe magnet. After the 

 coherer circuit has been closed by a spark, the slow approach 

 of a horse-shoe magnet will often open the circuit, precisely 

 as it does when the coherer has been closed by the magnet 

 held in a position of reversed polarity. When the magnet 

 fails to open the coherer circuit, the cause is either a too 

 rapid approach, which causes the coherer to close by a rever- 

 sal of magnetic polarity, or by a wrong presentation of the 

 magnet which confirms the condition produced by the spark 

 discharge. The conditions under which experiments are 

 made as yet, with the jarring due to the street traffic and the 

 explosions, and the changing magnetic field due to the electric 

 cars, have proven to be a source of some perplexity. It 

 throws some doubt upon the results reached. There, how- 

 ever, seems to be a residual effect which cannot thus be ac- 

 counted for, and it may be due to an ether displacement." 



* The Sun, p. 156. 



