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Astronomy. — ^'FreUininari/ Report on the Dutch e,vpedition to 

 Burgos for the observation of the total solar eclipse of 

 August 30, 1905," communicated by Prof. H. G. van de 

 Sande Bakhuyzen, in behalf of the Eclipse Committee. 



In March 1904 the Eclipse Committee determined to fit out on 

 a small scale an expedition to Spain to observe the total solar 

 eclipse of August 30, 1905. The means for it were found from some 

 liberal gifts of private persons and of societies (Provinciaal Utrechtsch 

 Genootschap, Teyler's Stichting, Utrechtsch Oud-Studentenfonds, Natuur 

 en Geneeskundrg Congres). As observers the same persons were 

 appointed who had been sent to Sumatra in 1901 : Messrs. W. H. 

 Julius, J, H. Wilterdink and the undersigned. The observations were 

 to include the spectrograph}' of the corona and of the sun's limb 

 and, provided a fourth observer should offer himself to join as a 

 volunteer, the radiation of heat of the corona. 



A volunteer was soon found in the person of Mr. Moll, assistant 

 for physics at Utrecht, and so the entire programme could be 

 worked out. 



The outfit of the expedition consisted of: 



a siderostat with a coelostat apparatus ; 



two slit-spectrographs, to be directed on the coelostat mirror ; 



a prismatic camera, to be directed on the northern polar mirror ; 



a heat actinometer; 



a pyrheliometer ; 



a sextant with accessories ; 



three chronometers and other auxiliary apparatus. 

 As the principal instruments were also used for the eclipse of 

 1901, I refer for the description of them to previous publications 

 (These Proc. Ill p. 529). 



The sextant and two of the three chronometers were kindly placed 

 at our disposal by His Excellency "de Minister van Marine" out of 

 the collection of instruments at Lejxlen. 



0.1 the 13^'' of August the party arrived at Burgos. This town had 

 been chosen for the observations not only on account of its favou- 

 rable situation and other outward advantages, but also because, as 

 far as was known at the time, it would not be visited by other 

 expeditions. These advantages were lost through the visit of H.M. the 

 King of Spain, on which occasion the town council of Burgos organised 

 a series of festivities which seriously interfered with the astronomical 

 work. For it is chiefly owing to those feasts that in spite of all 



