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endeavours we could get no assistants from among the educated 

 inhabitants of Burgos. At last one volunteer was found for the 

 spectrographic observations, and fortunatelj^ on the daj^ of the 

 eclipse some assistants offered their help; without this help the 

 measurements of the heat radiation especially would have been 

 entirely impossible. 



The eclipse has been observed under very untoward circumstances. 

 The station of observation, the hill Lilaila, at 3 kilometers south east 

 of Burgos (some 18 kilometers north of the central line) was a true 

 desert of sand where clouds of dust and sand were blown up by 

 the usually very strong wind, from which the tents, kindly lent us 

 by the Spanish war administration could only partly protect the 

 instruments. 



Especially the siderostat, which as a matter of course could not 

 be entirely covered, sufte red very much from the sand-storm ; although 

 it had been cleaned on August 29, the wheehvoi'k did not work 

 properly on August 30. The piers once being erected, it was impossible 

 to change the station of observation ; moreover, Lilaila oft'ered the 

 advantage that we could make use of the determinations of time 

 and geographical coordinates made by the Madrilenian astronomers 

 in whose camp our instruments were standing. 



The weather on the eclipse day was very unfavourable. The 1^^ 

 contact could not be observed owing to clouds, and though there 

 were some bright moments between the '1^^ and 2"'^ contact, the 

 observation of totality seemed hopeless. One minute before the 

 2"^ contact the rain ceased, the caps of the siderostat mirror could 

 be taken off, the clouds broke, and the corona was fairly visible 

 during 3V2 minutes, sometimes even clearly visible. 



Unfortunately totality began 20 seconds earlier than the computa- 

 tion had predicted, — it seems that also in Algiers and at other places 

 in Spain a fairly large difference has been stated between observation 

 and computation — so that the observers were taken by surprise by 

 the phenomenon, much to the detriment of a smooth carrying out 

 of the programme. 



For a detailed description of the observations I refer to the annexed 

 papers, which show that the results for some instruments, the very 

 unfavourable circumstances considered, may be called satisfactory. 



At the end of my report I Avish to acknowledge thanks to the 

 Madrilenian astronomers, who hospitably made room for us in their 

 camp and who were very obliging to us in all respects; to the 

 Spanish civil and military authorities who kindly allowed us exemp- 



