TERRESTRIAL MAGNETISM — BAUER. 273 



in from other stations. If it is found that the characteristic features 

 of this fluctuation did not take place simultaneously at widely dis- 

 tant stations, but progressed in accordance with the passage of the 

 shadow cone, the presumption will be strong that an eclipse effect 

 has again been detected. A fuller report must be reserved for a future 

 occasion, 



D. Magnetic Disturbances. 



For studying the correlation between solar phenomena and mag- 

 netic disturbances, cooperative work has been entered into between 

 the Solar Observatory and the Department of Terrestrial Magnetism. 

 Two direct recording variometers, giving a continuous visual record 

 of the magnetic fluctuations and ringing an electric alarm for dis- 

 turbances of a certain magnitude, have been constructed under the 

 direction of Dr. W. G. Cady, research magnetician, in accordance 

 with his design. One of these instruments has been supplied to the 

 Solar Observatory and the other was used by Dr. Cady at Black 

 Point, Nova Scotia, in connection with the eclipse observations. 



This may be a promising step toward working out a general plan 

 for enlisting in magnetic work the cooperation of certain favor- 

 ably situated and well-established institutions, such as astronomical 

 observatories, in order to assist in bringing about a more uniform 

 distribution of stations contributing magnetic data. 



E. Atmospheric Ei.ectricity Work. 



To enable the department to keep in touch with the latest develop- 

 ments in this work, Mr. J. E. Burbank, magnetician, spent three 

 months last spring in Germany in order to secure the necessary train- 

 ing under the guidance of Professors Elster and Geitel, of Wolfen- 

 biittel, and Professor Wiechert and Dr. Gerdien, of the University 

 of Gottingen. Every facility and courtesy were extended by these 

 gentlemen to Mr. Burbank, on account of which and for other aid 

 rendered the department is under grateful obligation. A proposal 

 having the indorsement of these eminent investigators regarding the 

 work in atmospheric electricity which the Institution may find it 

 beneficial to encourage will be submitted at a later occasion. 



Mr. Burbank, while abroad, likewise attended to the purchasing 

 and testing of magnetic and electric instruments for the department, 

 and also familiarized himself with the highly interesting work in 

 seismology conducted under the direction of Professor Wiechert at 

 the Geophysical Institute, which occupies such an enviable position 

 in geophysical research. On his return he made a successful and 

 important series of atmospheric electricity observations at sea, an 

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