44 REPORTS ON THE STATE OP SCIENCE. — 1915. 



Guildford and Malta. A proper investigation of the meteorological 

 conditions accompanying or determining the periods when strays are 

 heard simultaneously at places very wide apart has not yet been made. 



Auroral Displays and Strays. 



By the kindness of General Geo. P. Scriven, Chief Signal 

 Officer of the United States Army, the Committee have been able to 

 obtain reports from Officers in the Wireless Telegraph stations of 

 Alaska concerning the presence or absence of any connection between 

 auroral displays and disturbances due to natural electric waves or 

 atmospheric discharges. At six stations special observations have been 

 made during the later months of the past winter. Various types of 

 aurora were watched, but nearly all the observers reported that the 

 appearance or disappearance of auroras caused no unusual disturbances. 

 The best months for such observations in Alaska would, it is stated, be 

 October and November. The systematic work had not then been 

 started, but one telegraphist reports that during this period of more 

 brilliant display the only thing noticed in the radiotelegraphic apparatus 

 was a trifle more electrical disturbance than occurred when there was 

 no aurora. 



The 27-day Period of Magnetic Variations. 



Such of the radiotelegraphic records as were suitable for the purpose 

 have been analysed with a view to detecting a 27-day period in the 

 cases : days with many strays, nights with many strays, nights with 

 few strays. No trace of this period or of any nearly equal period has as 

 yet been found, but the matter cannot be regarded as settled till more 

 numerous and more continuous records are available. 



The Committee desire to express their coi'dial thanks for the help 

 extended to them by the Government Departments, companies, and 

 private individuals named below. The list refers to those whose co- 

 operation has been of importance in the matters described in the preced- 

 ing pages, and does not include the names of those who have helped in 

 other investigations. The assistance of the latter will be duly acknow- 

 ledged in future Reports. 



The British Admiralty and Post Office; the Colonial Office; the 

 Governments of AustraHa, Canada, and New Zealand; the War Depart- 

 ment and the Navy Department of the United States of America; and 

 the Telegraph Department of the Dutch East Indies: the Marconi 

 Companies in England, Canada, and the United States and the Marconi 

 International Marine Communication Company; the Eastern Telegraph, 

 Eastern Extension, and African Direct Telegraph Companies ; H. Bark- 

 hausen, W. G. Cady, E. T. Cottingham, D. O. Davies, E. H. Dixon, 

 E. D. Evens, J. P. Pennelly, A. Gorham, P. Kilbitz, J. R. Lamming, 

 ti: ^■. Lomas, P. A. Love, E. R. Macpherson, T. J. Matthews, W. E. 

 Nicoll, P. E. Norns, R. Ricci, D. Rintoul, C. Ross, A. Hoyt Taylor. 



